Rock to Hide Me

Those Magnificent Men and their Atomic Machines

Rock to Hide Me: Herman Kahn, Civil Defense, and the Manhattan Shelter Study

With Special Thanks to the Staff of the US Fire Administration Library

“One can almost hear the President saying to his advisors, 'How can I go to war – almost all American cities will be destroyed?' And the answer ought to be, in essence, 'That's not entirely fatal, we've built some spares.'” -Herman Kahn^[K]

Note on Notation

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The Early Years of Civil Defense

In December of 1950, President Harry S Truman announced the formation of the Federal Civil Defense Administration (FCDA). With UN forces falling back before the Chinese onslaught in Korea, world war – nuclear war – seemed imminent. The FCDA's mission was to protect American citizens if that war should come.

The crisis receded; the UN forces threw the Chinese back and the war settled into a long stalemate. But the larger threat of the Soviet Union remained, and the possibility of a surprise attack – a bolt from the blue, an atomic Pearl Harbor – was an almost universal fear, a fear the FCDA was supposed to deal with.

Truman's FCDA proposed to protect citizens with a network of government-built bomb shelters. But, with the stalemating of the war in Korea, Congress refused to allocate funds to actually build any shelters, and the whole concept of public shelters was abandoned with the arrival of the Eisenhower administration and the hydrogen bomb in 1952. The enormous power of the H-bomb – a hundred to a thousand times greater than the bombs dropped on Japan – led to a seemingly inescapable conclusion: the cities were doomed. Bomb shelters were pointless; they simply could not be made strong enough to survive, not for a price Congress or the fiscally conservative Eisenhower administration were willing to pay.

Eisenhower FCDA administrator Val Peterson argued instead that the only defense was “not to be there” when the bomb went off. When the Distant Early Warning RADAR stations spotted an incoming attack, every city in the nation would empty, the population moving en masse by bus and private car to receiving areas in the countryside in the few hours before the bombers arrived. Evacuating millions of people in a few hours was a mind-boggling logistical task – and, sooner or later, intercontinental rockets arcing over the North Pole would reduce those hours to thirty minutes.

Then, in 1954, a US nuclear test in the Pacific overshot its projected yield. CASTLE BRAVO spread radioactive contamination a hundred miles downwind, sickened dozens of Japanese fishermen and Marshallese islanders, and made horrifically clear that distance alone would not protect the evacuees. Fallout from high-yield nuclear surface-bursts would make large areas lethally radioactive for days or weeks. Even if the cities were successfully evacuated, the evacuees would still have to be provided with shelters.^[Bl][Mc]

By 1956, Val Peterson had changed his mind and asked President Eisenhower for $32.4 billion ($270 billion) to build public blast and fallout shelters. President Eisenhower responded by appointing a committee, commonly called the Gaither Committee after its chairman, to study not just Peterson's proposal, but the whole question of civil defense. At the committee's first meeting in August 1956, he set them a simple question: “If you make the assumption that there is going to be a nuclear war, what should I do?” The committee soon expanded its mandate to cover all aspects of this question, reviewing the United States' entire defense policy, but civil defense remained a core issue.^[Bl][Ka][Gh]

The FCDA and the Gaither Committee were not the only people thinking about how to protect the civilian population. With civil defense policy in flux, a new voice entered the debate – a young, roly-poly nuclear strategist named Herman Kahn. In 1956, a member of Kahn's civil defense group at the RAND think-tank proposed a radical new solution to the problem.^[Gh] There would not be time to flee to the countryside – but, if city-dwellers could not escape horizontally, perhaps they could escape vertically.

A vast network of deep underground tunnels and dormitories could be built under every major urban area in the country. When warning came, every man, woman, and child would descend 800 feet into the earth, deep enough to survive a direct hit by a high-yield nuclear weapon. There they would remain for three months until the radiation in the city's ruins dropped to safe levels. The project would be preposterously expensive, requiring excavation and construction on a titanic scale – engineering commensurate to the scale of the problem it was intended to solve. But its inventors believed it could ensure the survival of 86% of the American people, even in the face of all-out thermonuclear war.

Figure 1: Model of Manhattan Shelter Study^[Pa]

(Copyright Expired)

Herman Kahn and Robert Panero

Located near the beach in Santa Monica, California, in an incongruously mundane pair of office buildings, the RAND corporation was the stomping ground of the first generation of Cold War nuclear strategists. Under the bright California sun, mathematicians, physicists, economists, and social scientists studied how to prevent, fight, and win a nuclear war.

Herman Kahn was, at least in the public's eyes, the quintessence of the RAND think-tankers. Born in 1922 to Polish immigrants of humble circumstances, he had completed his Bachelor's degree in physics at UCLA before being drafted in 1943. He returned to California after the war and joined RAND in 1947 while studying for his Ph.D. in physics, working on – among other things – mathematical modeling of hydrogen bomb designs.^[Ka][Gh]

Most RAND physicists didn't involve themselves in the “soft science” of strategy, but Kahn was different. His irrepressibly inquisitive nature led him outside the gated physics community, into such matters as whether SAC bombers could penetrate Soviet air defenses. But it wasn't until 1953, when he married Rosalie Jane Heilner, that he turned his attention fully to matters of strategy rather than physics. The FBI viewed Heilner's sister and her husband as “known Communists”, and they revoked Kahn's security clearances, including his precious “Q” clearance allowing access to the Atomic Energy Commission's (AEC) hidden mysteries. His Top Secret clearance was restored eight months later, but his Q clearance remained in limbo. Without access to AEC data, Kahn could do little work in physics, and turned more and more to nuclear strategy. By the time his full clearance was restored in 1955, the new direction in his career was set.

Although widely cited as the inspiration for Stanley Kubrick's Dr. Strangelove, in real life Kahn was rotund, jovial, and relentlessly talkative, speaking so fast he would trip over his own sentences. He dazzled listeners by the sheer speed of his arguments as well as with their content, mixing black humor and mathematical analysis into a potent concoction.^[Gh]

Figure 2: Herman Kahn^[LoC]
(Public Domain)

Kahn would achieve notoriety later in life; he was the only RAND strategist who became a public celebrity. He was a particular bete noire of the peace movement, who despised him as an American Eichmann, eagerly planning the Apocalypse. Despite his reputation, those who actually met him often couldn't help but be charmed by his personal manner, his willingness to engage with even the most radical of critics. He regularly corresponded with peace groups such as the Committee for Non-Violent Action and the Committee of Correspondence, spoke approvingly of the hippie counterculture, and boasted of having tried LSD.

Arguably, Kahn's great sin was not so much what he said as how he said it. There were many others who advocated the same ideas, but few of them had demonstrators picketing their house. Kahn, though, treated nuclear war with seeming frivolity, tossing off projections of hundreds of megadeaths with a bad joke. He refused to intermingle his arguments with apologia for the grim calculus of nuclear strategy, preferring to maintain the surgeon's detachment and black humor. To his critics he seemed inhuman, if not eagerly genocidal. Kahn seemed to relish the notoriety – Steuart Pittman, Kennedy's assistant secretary for defense for civil defense and a friend of Kahn's, said he “really wanted to be cursed and damned. He just gloried in it.” But all that would come later; in the late 50s he was just another RAND think-tanker, not yet in the public eye.^[Gh]

Kahn was part of a group of theorists advocating an alternative approach to nuclear strategy. Since the election of President Eisenhower in 1952, the official US strategic doctrine had been Massive Retaliation. The United States, in the view of the Eisenhower administration, could not afford to maintain land forces capable of going toe-to-toe with the enormous Red Army. Instead, in the event of armed conflict with the USSR, the United States would unleash Strategic Air Command (SAC) to devastate the Russian heartland with nuclear weapons, attacking both their military and civilian infrastructure – which would necessarily involve the slaughter of tens of millions of Russians.

Kahn, among others, believed this strategy was fundamentally unworkable. Would an American president really be willing to unleash SAC if Soviet troops crossed into Germany? Or Berlin – would American leaders really be willing to risk national destruction to save a single city? Massive retaliation left the US with only two options: bluster or apocalypse, with the war plann reduced to simply throwing everything at the enemy all at once – Kahn (echoing Bernard Brodie) disparaged it as replacing a war plan with a “war orgasm”.

In Kahn's view, the United States needed options, flexibility, ways to respond militarily to Soviet aggression short of a massive nuclear exchange. A properly designed strategy would seek to control the escalation of a conflict even after it had begun, to limit it to some level below deliberate mass murder of civilians. He outlined three types of deterrent capabilities he felt the United States needed: “Type I” deterrence, the ability to burn Soviet cities if all else failed, which would deter the Soviets from attacking the US itself; “Type II” deterrence, a Credible First Strike Ability, the ability to destroy as much as possible of the Soviet nuclear arsenal on the ground in a preemptive attack, which would deter the Soviets from provocative actions short of what would trigger a Type I response; and “Type III” deterrence, the ability to take limited measures against actions short of what would trigger a Type II response, ranging from economic sanctions to limited nuclear strikes.^[K]

Without Type II and III deterrence, Kahn feared the USSR would be able to use its conventional superiority to conquer whomever they pleased; the US threat to retaliate with nuclear weapons would not be believable, since retaliation would mean our own destruction.^[Ka]

Where Kahn differed from other Limited War strategists was in adding civil defense to the mix. Kahn became interested in civil defense around 1956, the same year the Gaither Committee began meeting. RAND launched a major study that year on how to best structure the strategic bomber force. Kahn persuaded his superiors at RAND to allow him to run a side-study on civil defense, despite the opposition of the company's president, Franklin Collbohm. According to Kahn, Collbohm “had ideological objections to civil defense, as did the Air Force, and his objections were very personal – he was director of civil defense at Douglas [during WWII] and had done some very stupid things.” Nonetheless, after much argument, they allowed Kahn his study, although the Air Force wouldn't pay for it – instead it would be funded by a grant from the Ford Foundation.^[Gh]

Kahn saw value in civil defense for the traditional reasons of damage limitation – after all, no matter how clever the strategist, no one could guarantee a nuclear war would not occur. But it also served a role in his geopolitical strategy. Without civil defense, Type II deterrence was not believable. Even a badly damaged and disorganized Soviet retaliation would kill millions of Americans if they were not provided with shelters; thus no president would ever be willing to order a first strike, and so the Soviets would not be deterred by the capability since it could never be used. Civil defense made deterrence possible by making a nuclear threat believable.^[Ka]

Kahn's partner in the civil defense project was a young engineer named Robert Panero. Engineering was a family trade for Panero. Born in 1928, he was the son of Guy B. Panero, who had founded a successful engineering firm in New York City.^[CBR] Guy B. Panero Engineers had consulted on everything from Rockefeller Center to the National Gallery of Art to Royal Medical City of Baghdad in Iraq.^[NYT] The firm's involvement with civil defense dated to at least 1948, before the Federal Civil Defense Administration had even existed, when they had produced a series of reports for the Army on moving strategic industrial installations underground.^[Pa2] Robert Panero's childhood had been spent in New York, Ohio, Tennessee, and Europe, following his father from one project to another.^[Mi]

Panero joined the family firm after serving in the Army in the early 50s, where he helped to design the United States' first factory for producing nerve gas.^[Mi] He worked with the RAND Corporation as part of Guy B. Panero Engineers' Special Projects Group from 1956 to 1960, becoming involved with Kahn's civil defense project some time in 1956 or 1957.^[CBR]

Who first suggested the deep urban shelter concept is lost to history. But for 1957, it would be Panero's baby. With Kahn's backing, Robert Panero and his father's firm would spend the year studying how to shelter an urban population deep underground, using Manhattan as a case study.^[Gh] Manhattan was chosen because it was seen as one of the most difficult cities to build such a shelter system in; therefore, if it proved feasible in Manhattan, it presumably could be made to work anywhere. Although the study started as a RAND project, at some point the contract was taken over by the Federal Civil Defense Agency, who paid Guy B. Panero Engineers $18,000 ($141,000) to complete it.^[CGO]

Moving Underground

I was only able to obtain one of the study's two volumes, plus the appendix. The first volume discusses the Manhattan Shelter; from the appendix, the second volume appears to have dealt with how to extend the concept to other cities, using mines and other existing underground structures. Given the vast scope of the project, the study necessarily skimmed over many details, painting in broad outlines.

Panero and co. were not tasked with designing a shelter network to withstand any level of attack. Instead, they were told to design a shelter system for Manhattan island that:

• Was located 800 feet deep underground;
• Could be fully occupied with thirty minutes of warning;
• Could support its inhabitants for 90 days;
• And could support the entire population of Manhattan – four million people.

The initial phase of the project studied the geology and population density of Manhattan. Based on the results from this phase, Panero Engineers decided to use 25 separate “base modules”, holding up to 160,000 people each. Shelters were located based on daytime or nighttime population densities, whichever was higher for the area.^[Pa]

Figure 3: Cutaway View of Base Modules Under Manhattan^[Pa]

(Copyright Expired)

The governing factor in locating the base modules was the need to get the entire population underground within thirty minutes. If sensors detected an approaching attack, air raid sirens would sound to alert the populace. (More dramatic measures were also considered, such as detonating a small nuclear bomb above the city as a giant signal flare.^[RAND]) New York City elevators of 1958 were designed to shift 25% of the building's population every five minutes. Using staircases instead of elevators would allow a faster evacuation, but, to be conservative, Panero and his team assumed that the last people would make it out of their buildings twenty minutes after the warning siren sounded.^[Pa]

Figure 4: Map of Manhattan Shelters^[Pa]

(Copyright Expired)

Panero determined walking speeds by timing people's movement at Grand Central Station, Liberty Street ferry entries, and other Manhattan locations, ending up with a speed of 300 feet per minute. Therefore, to ensure the entire population could be inside the blast doors within thirty minutes, every point on Manhattan would have to be within 3,000 feet of a shelter entry – 2,000 feet to allow a margin of safety. This would require 92 entry portals: 75 standard entries, 20 feet wide and 12 to 14 feet high, and 17 larger entries for higher-density areas, 40 feet wide and 18 feet high.

The portals would be marked with 25-foot-tall pylons, shaped like a cone or pyramid and lit with 2,500 to 10,000 watts of light. Each portal would open into a steep (1 foot down for every 4 feet across) tunnel leading to a base module, lit with fluorescents tinted to feel like a “welcome glow”. Some tunnels would also have conveyor belts for the elderly and infirm. The tunnels could be sealed at top and bottom with blast doors rated to 500 psi of overpressure – almost as strong as a missile silo – and rigged to collapse if the upper door failed, to keep the blast wave from reaching the shelter below.^[Pa]

Figure 5: Shelter Entry^[Pa]

(Copyright Expired)

Figure 6: Cutaway of Shelter Entries^[Pa]

(Copyright Expired)

In theory, everyone in the city could be behind the upper blast door thirty minutes after the siren sounded, and behind the lower blast door and inside the shelter five to ten minutes later.

Once inside the shelter, civil defense personnel would process the fleeing citizens and assign them to shelter dormitories. They would then remain underground for up to three months.^[Pa]

Living Underground

Each of the twenty-five bases would be split into six modules: five dormitories of 31,000 people each, and a central headquarters module holding 5,000 people and acting as a “'municipal' center” for the base module's 160,000 occupants. The headquarters module included a 500-bed hospital, 41,600 ft² command section fitted with electric typewriters, tabulating machines, and other office equipment, two police stations manned by 1,000 security personnel, mechanical and electrical support stations, storage areas, and a laundry.

A tunnel would run transversely between the modules, serving as a main road and splitting them into pairs of submodules of 15,500 each. Each base would be operated and maintained by 15,000 “cadre workers” - 5,000 in the headquarters and 2,000 in each submodule.^[Pa]

Figure 7: Shelter Base Module^[Pa]

(Copyright Expired)

The modules would be 975 feet by 550 feet by 22 feet chambers, lined with concrete and supported by rock pillars. 31,000 people would live in a gross square footage of 536,250, or 268,120 ft² if you subtract the rock supports. Eight 18,000 ft² dormitories housing 3,625 people each would be laid out on the edges of the module. Each dormitory would be 30 feet wide, 600 feet long, and 20 feet high, and hold bunks stacked four high. The dormitories would each be further subdivided into two sub-dormitories, and then into three “basic groups” of 600, which would operate as a “neighborhood unit or block.” Blocks would be painted different colors – gray, blue, yellow, etc – and each block would share times for mess, exercise, bathing, work, etc. Lockers would be provided for storage of whatever personal belongings the occupants had. Lighting would be provided by fluorescent lamps. Showering would be in groups.

Leaders would be selected among each block's residents to help the shelter cadre in “creating general harmony, morale, and effectiveness, as well as solving the group housekeeping problem.” The authors acknowledged that, after food, air, and other necessities, it would be vital to preserve “an environment conducive to psychic health under crisis conditions.” They suggested easing the adjustment to life underground with “an appropriate choice of materials, colorings, and finishes”, but left the specifics to future studies.^[Pa]

Figure 8: Dormitory Cross-Section^[Pa]

(Copyright Expired)

Besides the dormitories, the submodules would each have a police station, shower and clothes changing and issuing area, mess area, kitchen, a 60-bed hospital including dental clinic, and an 18,000 ft² exercise area and park, as well as separate housing for shelter cadres. The 6,000 ft² police station would include space for 100 security personnel and two small prison blocks.^[Pa]

Figure 9: Shelter Submodule^[Pa]

(Copyright Expired)

Every shelter occupant would be alloted one hour of exercise time per day. The exercise area would be supplied with sports equipment and high-power lighting simulating sunlight. Mass exercises such as gymnastics would be encouraged.

Since the occupants would have only the clothes they were wearing when the sirens sounded, shelter workers would issue them garments when they first arrived at their dormitories: two sets of overalls and underwear, possibly color coded with their block color and rank. Clothes washing would be limited to one set of clothes every four days, with the washing machines powered by steam from the power plant cooling system.

There would be only one hot meal per day, eaten with paper plates and plastic utensils in the mess area. A different group would eat every hour, with the mess operating twenty four hours a day. The other two meals would be eaten cold - “3-1/2” x 11” cylindrical capsule rations” - in the dormitories or exercise area. The study provides no details on the nature of the hot meals, although it does mention that no provisions would be made in the kitchens for “baking, broiling, salad preparation, meat cutting or potato peeling”. Like the laundry, the kitchen's heat needs would be supplied by power plant steam.^[Pa]

Figure 10: Mess Area^[Pa]

(Copyright Expired)

The “main road” tunnel would also connect the base to its neighboring bases, for maintenance and supply and so that people caught by the attack away from home would not be separated from their families. Secondary tunnels at a lower depth would supplement the main inter-base tunnel, easing traffic congestion and providing a backup route if a base were lost. The authors hadn't decided on the specific means of transport, but considered elevated walkways (to keep foot traffic from clashing with vehicles), battery-operated cars and trucks, bicycles for individuals, a “special suspended system” for police traffic, and monorails for supply movement.^[Pa]

Figure 11: Main Road Tunnel^[Pa]

(Copyright Expired)

Surviving Underground

The 25 base modules of Manhattan would be overseen from a General Headquarters, commanded by a Supreme Commander, who would be either the mayor or the civil defense chief of New York City. Under him would be the Module Group Commanders, each overseeing five modules, a General Advisory Staff, and a General Services Staff. The General Services Staff would primarily be responsible for keeping the electricity, water, and sewage systems functioning, as well as communications, data processing, finances, accounting, and other tasks – even the apocalypse would not end the requirement for proper paperwork.

The shelters would need 400 megawatts of electrical power to keep everything running. The only realistic option was atomic energy – gas, coal, or oil would require air for combustion, and batteries couldn't hold out for three months. Four 100 MWe pressurized water reactors, each ten times the size of the USS Nautilus's propulsion reactor, would supply the electricity. Each power plant would have a 1 MWe backup diesel generator to provide power for reactor start up if the electric grid was unavailable. Hydrogen fuel cells would supply emergency power to the shelters if the reactors went offline.

Although the engineers decided for the purpose of the study to space the reactors equidistantly around the island, they strongly recommended considering placing the reactors outside the city limits and connecting them to the shelters via an underground power line. Given the high cost of atomic reactors – which were still brand-new technology at the time – they would be much easier to pay for if they supplied power to the grid during peacetime, and it was unlikely the Atomic Energy Commission would license reactors inside city limits for non-emergency use. Also, given the large amounts of water needed to cool the reactors' steam condensers, it would be very helpful to place them closer to the surface and near a river to reduce pumping requirements, rather than deep under Manhattan.

Besides electricity, the shelter's air would have to be purified of carbon dioxide and oxygen added. A number of approaches were considered, with the engineers settling on sodium superoxide (NaO₂), which would react with carbon dioxide to produce oxygen. About 50,000 tons of the material would be needed for each base module. Sodium superoxide reacts violently with water, requiring careful storage, but it could be procured at a comparatively reasonable price of only $20 million ($157 million) per base module and it eliminated the need for separate systems for scrubbing carbon dioxide and replenishing oxygen.

The shelters would also need 600 million gallons of water per day – an Olympic swimming pool every 95 seconds. Only 12 million gallons would be needed for drinking and cooking; five-sixth of the supply would be for air conditioning and cooling the reactor steam condensers. 800 feet of rock is an excellent insulator; without a way to dispose of waste heat, the shelter residents would rapidly cook. The air conditioners would need 420,000 gallons of water per minute to remove waste heat, not counting the water needed for reactor cooling; fortunately the same water could be used for both purposes. After absorbing its load of waste heat, the water would be pumped into the city's sewer system, along with the shelter sewage; the engineers believed that, even if the sewer system was destroyed, enough void space would remain in the rubble to absorb the liquid.

Multiple redundant sources were planned for the water supply. The first source would be the reservoirs and watersheds already in use – the Delaware, Catskill, and Croton systems. The Delaware alone could supply enough water for all needs, and its water was already carried by underground tunnels resistant to blast. The Catskill and Croton systems were too small to serve by themselves – and the Catskill supply line included aqueducts near the surface vulnerable to attack – but they could provide enough water together if they survived but the Delaware did not. In all three cases, the water was actually delivered to the city through 200-foot-deep tunnels that should survive anything except a direct hit; however, to minimize vulnerability, it was recommended that a new, 800-foot-deep tunnel be dug for emergency use. In addition, the various connecting and control stations would have to be hardened against attack.

However, it was impossible to absolutely ensure the reservoirs would not be contaminated by fallout or the tunnels or pumps destroyed. Water might be collected from deep seams or rock faults, but the authors didn't know if there was enough water under Manhattan or, if it was there, if it was drinkable. Water might also be collected from the Hudson river, but this could only be drunk if fallout was speedily swept out to sea, and no one knew how long that would take. Even contaminated or unpotable water could probably be used for cooling, though, and if all drinkable water sources were put out of action, three underground reservoirs of 90 million gallons each would supply water for drinking and cooking.^[Pa]

The total cost estimate for the system for Manhattan was $2.7 billion ($21.1 billion), or $680 ($5,325) per person. This included $713 million ($5.6 billion) for excavation and $1.3 billion ($10 billion) for the nuclear reactor, water system, and other utilities. The report estimated that 2½ years would be needed for excavation, but did not provide a time for outfitting the shelter once it had been dug. However, in Congressional testimony, Benjamin Taylor of the FCDA suggested it might be possible to finish the entire national system in two to three years, given a sufficiently motivating emergency.^[Pa][CGO]

The Gaither Committee

Kahn wasted no time in sharing the good news. He was in Washington before the study was even finished, telling the Gaither Committee's working group on civil defense all about it, and asking them to recommend the construction of deep shelters for 50 million people, along with shallower blast shelters for 50 million people and unhardened fallout shelters for 100 million. And not just shelters for people – factories could be moved underground, stockpiles gathered, research programs initiated. With proper preparation – and enough money – the United States could be equipped to fight, survive, and win a nuclear war. Kahn recommended a budget of $200 billion ($1.6 trillion) for the project.

Kahn's proposal backfired, massively. Spurgeon Keeny, the leader of the civil defense group, later recalled that “the biggest influence Kahn had on me was showing what a huge undertaking civil defense was, and many of the limitations of what it could do... I had never really thought about it quantitatively. As one studied it in some detail, the utility of blast shelters became increasingly dubious.”

Kahn's preliminary cost figures were mind-bogglingly expensive – about half of the nation's total economic output in 1957. And those figures were almost certainly overly optimistic. Paul Seyfried, an engineer with over 25 years of experience in building bomb shelters, pointed out that “every cost estimate is way low... The F-18 was supposed to cost $4.5 million flyaway cost, and it ended up costing $40 million.”^[Se] John Doe, a former government contractor with experience in nuclear weapons and shelter construction who prefers to remain anonymous, said that by “rough, very rough calculations” he would estimate the real cost would be “about 6 times higher.”^[An]  The time estimates were even less realistic – Doe said the estimated construction time of two to three years was simply “not plausible”^[An]; Seyfried commented that “they couldn't build twenty miles of interstate here along the Wasatch front in three years.”^[Se]

And the impact on society as a whole would not be limited to the financial drain. In the Manhattan Shelter Study, almost one in every ten people was supposed to be recruited as “civil defense cadres.”   The character of the cadres is not specified, but it is hard to see how they could be organized except as a quasi-military force. As Keeny put it, “we became increasingly convinced that the distortion of society [by this] would be such [that] no one would tolerate it... There was no longer any question but that in a nuclear war you would lose the whole society, even though you could save lives with fallout shelters. The whole experience was extremely disturbing to me and many of the other participants. Was this really a way to solve the problem? The proposed solution seemed to lead to a garrison state.”

By advocating for such a massive program, intended to protect everyone from everything, Kahn only succeeded in discrediting more sensible concepts. Congressmen at a hearing in early 1958 mocked it as “gold-plated”, “strictly de luxe”, and “competing with the moles.” Representative Chet Holifield demanded to know “why you indulge in such a fantastic study when the problem faces the Nation of giving protection to the maximum number of people? The only thing that I can see that such a study as this would bring about is such a completely fantastic picture, such a fantastic story that it could be used to ridicule the whole proposition of giving the people of this Nation a reasonably attainable and safe type of shelter...”^[CGO]

The Gaither Committee presented its report on November 7^th, 1957. They endorsed $25 billion ($201 billion) for fallout shelters as “likely to save more lives for the same money in the event of a nuclear attack” than any other measure, but recommended against blast shelters, believing the money to be better spent on active defenses such as interceptor aircraft and surface-to-air missiles. But they assigned highest priority, over and above any defensive measures, to strengthening the military's offensive capabilities to keep a war from happening in the first place.^[GC]

President Eisenhower's response was gloomy. He thanked the committee for their work, but said that he did not “believe that American society could survive and reconstruct from a nuclear war... You can't have this kind of war. There just aren't enough bulldozers to scrape the bodies off the streets.”^[Gh]

Would it Have Worked?

The Manhattan Shelter Study was published in April 1958, although a preliminary version was circulating earlier.^[Pa] The FCDA commissioned a followup study by the Armour Research Foundation (ARF), to determine whether the shelters would actually survive under attack. The FCDA asked the ARF to determine how much damage a shelter would suffer if a 20 megaton hydrogen bomb was burst on the surface directly overhead, with the expectation that such a weapon would not “have any serious effect.”^[CGO] The ARF study was published in November of 1958.

When a nuclear bomb is detonated, it produces a staggering amount of energy – the equivalent of thousands to millions of tons of conventional explosives – in about a millionth of a second. For a fraction of an instant the roiling ball of plasma that was the bomb reaches temperatures of millions of degrees Celsius. The heat vaporizes any solid material near the bomb and superheats the air, forming a fireball. The expansion of the fireball pushes against the air and ground, creating a shockwave that passes through them.

The fireball creates an initial strong but localized shock around the point of detonation. The blast wave passing through the air also strikes the ground around the detonation as an “air slap”, creating a wider but weaker load. The localized shock blows earth out of the blast zone, creating a crater, and fracturing the rock in a “rupture zone” around the crater itself. Survival at the edge of the crater is theoretically possible for unmanned structures, but the shaking would likely kill any human occupants.

Figure 11: Typical Nuclear Crater Cross-Section^[FFL]

(US Government)

The shockwave passes through the earth beyond the rupture zone at the speed of sound. People in structures beneath the blast would feel a short but very intense earthquake. Besides shaking, the pressure wave would cause spalling from shelter roofs, breaking off rock and, if the pressure is strong enough, collapsing the tunnel.

The degree of damage depends on how the ground interacts with the shockwave – how quickly energy is leeched from it as it travels – and by how the shockwave will interact with the tunnel. This is a complicated subject, still not fully understood even today. Data had been gathered from nuclear weapons tests at the Nevada Test Site since the JANGLE shots in 1951, and from tests using conventional explosives, but the models available in the late 50s were still very crude, and most research had focused on how nuclear explosions effected above-ground structures.^[Br] Based on admittedly primitive calculations, the Armour Research Foundation concluded that a 500-kiloton nuclear weapon detonating on the surface 800 feet above a Panero-style shelter would cause light damage. A 2.2-megaton weapon would cause moderate damage, while a 13-megaton weapon would cause heavy damage.^[ARF]

Modern approaches to calculating ground shock damage use complicated computer models that are not available to the public. But the output of some of those models are known: in an evaluation of a proposed earth-penetrating nuclear weapon published in 2005, the National Academy of Sciences included calculations of ground shock in granite for a 5.6-megaton nuclear weapon detonated on the surface. In these models, damaging effects are measured in terms of quantities called “peak free-field strain” and “peak free-field velocity”; a peak strain of 0.15% to 0.2% and peak velocity of 5 to 15 meters per second has a 50% chance of causing a 10 to 20 meter-diameter, modestly hardened tunnel to collapse. The large cavities of the Manhattan shelters would be weaker than tunnels of this description. According to the model, the peak strain at 800 feet exceeds 0.5% and the peak velocity exceeds 10 meters per second. Under these conditions, it is unlikely the shelter would survive.^[NAS]

Thus, at first glance, it appears that the concept was a bust, given that it would not hold up under attack. But, the astute reader will point out, in actual fact neither the US nor the Russians actually deployed very many of these high-yield weapons; modern thermonuclear bombs are typically less than a megaton in yield. The problem with this argument is that, historically, few high-yield weapons were built because most targets could be destroyed by smaller bombs. If the US had actually built deep shelters of this sort, in all likelihood the USSR would have built correspondingly larger weapons to attack them.

But, the counter-argument continues, while the shelters might be vulnerable, even a large bomb would be unlikely to destroy more than one. Since each shelter would have to be attacked individually, the Soviets would have had to allocate twenty-five times as many weapons to destroy Manhattan. And, since typical ICBMs can only carry a single warhead of multi-megaton yield – in comparison to four or more smaller bombs – the Soviets would have had to build about 100 times as many missiles for the purpose of attacking cities as they actually did, a very expensive proposition.

But building more missiles would still have been cheaper than building the shelters.   If each shelter was targeted with 4 20-megaton warheads, the Soviets would need 100 missiles to destroy Manhattan.   A Minuteman III intercontinental ballistic missile costs $29.4 million in 2012 dollars^[NWA], so 100 of them cost about $2.9 billion. The shelter system for Manhattan alone would have cost $21.1 billion, more than seven times as much. A defense that costs you $7 which your enemy can counter for $1 is usually not a wise investment. Furthermore, the Soviets would not have had to destroy the shelters themselves to kill their occupants – knocking out the power plants, the water supply system, or the pumping stations to return water to the surface would have the same effect, but require far fewer bombs.

Alternatively, the shelters could have been excavated deeper, beneath the ground shock radius of a 20 megaton warhead, or built with a stronger tunnel lining that could resist a heavier shock. The ARF report suggested that, with strong tunnel linings, a shelter module could survive without serious damage in the heavy damage zone^[ARF]. In principle, such a shelter could still be destroyed, but it would require using one warhead to excavate a crater above it, then landing a second warhead inside that crater – followed, perhaps, by a third, a fourth, etc., to dig out the target. But this would require great accuracy and precise timing, which was not achieved until late in the Cold War. And at some point the attack becomes impractical, if only because the crater walls become steep enough that succeeding warheads collide with them before they hit the bottom. Although the Manhattan shelter as designed might be too shallow to survive attack, the concept could perhaps be rescued by digging deeper...

Except that this would increase the cost of an already staggeringly expensive program still further. And even if the shelter was built deep enough to survive attack, it would take thirty minutes for citizens to enter the shelters, the flight time of an ICBM. But a submarine-launched ballistic missile gives far less warning – typically ten minutes, less if attacking from short range on a depressed trajectory. The entry time into the shelters could be reduced somewhat by building more entrances, but not to less than ten minutes. The majority of the population would be killed before they could even leave their buildings. No matter how much money was spent digging holes, bomb shelters – no matter how deep – could not save Manhattan's citizens from a surprise attack.

Given warning of an attack before it was launched, the population could be moved underground. But there are few plausible scenarios in which the government would have thirty minutes of warning, but not several days of warning. Given a week, the people of Manhattan could be evacuated to shallow fallout shelters in the countryside. Such shelters would be less vulnerable, since they would be too dispersed to be practically attacked, and they would be far, far less expensive.

While more mundane civil defense measures such as food stockpiling and shallow fallout shelters could save many millions of lives, it is difficult to see how urban deep rock shelters could be effective, even if Congress had been willing to allocate the money to build them.^[An][Se]

Later On

Kahn's civil defense study was published in July of 1958. Report on a Study of Non-Military Defense was a short – just 58 pages – summary of a truly enormous topic, covering everything from shelter construction, to the long-term effects of radiation, to post-war reconstruction, all of which could have taken up many thousands of pages of their own.

The document sketched out two systems of public shelters. The light option provided only a small stockpile of critical supplies and shelters that protected only against radiation, and was estimated to cost $20 billion ($157 billion) over ten years. The heavy option included large supply stockpiles and fallout and blast sheltering. This program would go beyond even the deeply-buried urban shelters envisioned by the Panero study – for example, 20% of the national industrial base would be hardened against blast by moving it underground. Kahn priced the program at $149 billion ($1,167 billion) over ten years.

The report claimed that, in an attack on 150 American cities, 160 million people, out of a total population of 180 million, would die if not provided with shelters. The light sheltering option would reduce that to only 60 to 85 million deaths, depending on the amount of warning time – and the heavy shelters to just 25 million, assuming just 30 minutes of warning. If the warning time was increased to several days – enough time to evacuate the most vulnerable areas – casualties could be held down to just 5 million out of 180 million people. A terrible toll, worse than any other war America had been involved in – but also fewer than one in thirty people.

But Kahn did not actually recommend going ahead with the heavy blast shelter program. Perhaps by this time he felt the political headwinds against his massive shelter schemes, although if so it was unusual that he heeded them – he usually took delight in going against the prevailing wisdom. Instead, the study ended – as so many do – with a recommendation for further research and more studies, specifically for $200 million ($1.6 billion) per year to be allocated to further research^[RAND]. This would roughly triple the FCDA's budget.^[FCDA] Besides this, Kahn recommended changing the mission of federal civil defense agencies to de-emphasize mobilization (a relic of earlier times) and emphasize defense, adjusting the composition of existing defense stockpiles to better reflect post-war reconstruction needs, subsidizing the creation of mine space, and similar measures. But he did not recommend actually building any shelters until more data could be gathered – and certainly not the deep fortresses envisioned by Panero. As the report itself acknowledged, there was simply not enough data to make wise decisions yet, much less commit to the Herculean feat of engineering envisioned by the Manhattan Shelter Study.^[RAND]

In March of 1959, RAND held its Second Protective Construction Symposium. The focus of the conference was military rather than civilian, but it did include speakers from Guy B. Panero Engineers, including Robert Panero. Kahn introduced the symposium, briefing participants on his theories of limited war and the need for massive underground engineering works, musing on future deep bases and joking about Hollywood lionization of the Air Force and how they would treat a future “SUC”, or “Strategic Underground Command.”^[K2]

The next year, both Kahn and Panero had left RAND. Kahn published On Thermonuclear War, his magnum opus, outlining his Types of Deterrence and bringing him national infamy. By the end of 1960 he had founded his own think-tank, the Hudson Institute. Although he published several more books on nuclear strategy, after the early 60s his interests drifted away from war to more congenial topics like third-world development and futurism.^[Gh] Robert Panero left the US to head Guy B. Panero Engineers' Italian office. He returned to the US in 1964, joining Kahn at the Hudson Institute and publishing studies on topics like South American economic development, South Vietnamese welfare systems, and port facilities for the island of Palau.^[CBR] He retained his taste for mega-engineering, however, such as in a 1967 proposal to use large numbers of small earthen dams to create a “South American Great Lakes System”, reengineering the continent's hydrology to create navigable waterways, control erosion, produce electrical power, and irrigate crops.^[Pa3]

There is one final, nagging note to the story, though. According to a paragraph in the New Yorker, in 1960 the New York Academy of Sciences issued a press release detailing findings of the Manhattan Shelter Study.^[NY] This would presumably be right before Robert Panero left for Italy. Unfortunately, I have been unable to find any other information whatsoever on this press release or the reason why the NYAS was interested in the project, even after contacting the Academy themselves.

The Later Years of Civil Defense

Two years after the Manhattan Shelter Study ended, John F. Kennedy was elected the president of the United States. Kennedy had a personal interest in civil defense, and two emergencies in succession – the Second Berlin Crisis and the Cuban Missile Crisis – meant congress was willing to actually allocate money to the program. The 1962 budget for the FCDA – which by this point had morphed into the Office of Civil Defense – was more than twice its previous highest annual budget. Most of the money was spent on surveying existing buildings for rooms that could be converted into fallout shelters, stocking them with supplies, incorporating shelters into new federal buildings under construction, and subsidizing non-profits to include fallout shelters in their buildings. By November of 1963, 110 million potential shelter spaces had been identified and 14 million had been stocked.

But by 1963 the crises had passed, and the budget was cut in half, then cut again in 1964.^[Bl] Kennedy himself started to turn against shelters after an interview with Edward Teller that bore eerie similarities to Kahn's talk with the Gaither Committee, including advocating for massive deep rock shelters.^[Ka] After Kennedy's death the program passed into limbo once again, and never really revived.^[Bl]

One of the secrets of the Cold War is that a modest civil defense program really could have saved many lives if war had come. Beginning in 1963, the government of Switzerland mandated the inclusion of a blast shelter in every new home. By the late 80s, Swiss shelters could accommodate 83% of the nation's population, at a cost of $75 per person per year in 2012 dollars – equivalent to $23.5 billion per year in the United States.^[NYT2][Bl] While such shelters could not survive a direct hit from a nuclear weapon, or even a near miss, they would still save many lives in the event of war. Such a program was not cheap, but it did not require pouring trillions and trillions of dollars into caverns, either. So why did the US never build any shelters?

Fundamentally, I believe, people just didn't want to think about it. The threat of nuclear war is vast and terrifying, and anything an individual might do in the face of it seems meaninglessly insignificant. Furthermore, if bomb shelters reduced casualties from, say, 100 million to 50 million, that still means tens of millions of dead. Even if, mathematically, the cost of the shelters was clearly worth it, the mind tends to focus on the 50 million who died rather than the 50 million who were saved. Finally, even if a bomb shelter did save your life, the terrible damage that would be wrought to society, both physical and psychological, was awful to think about. As Kahn himself put it in 1960:

“I believe the basic reason for this lack of study of many important problems [in civil defense] is less irresponsibility or incompetency than the enormous psychological difficulty which everybody has of coming to grips with the concept of thermonuclear war as a disaster that may be experienced and recovered from. It seems to be much better to deter the event. Peace seems so desirable and war so ridiculous. Everybody prefers to spend his time thinking about the prevention of war by deterrence or negotiation.”^[K]

For all of these reasons, most people preferred to put the possibility of war out of their minds, to focus on their day-to-day lives rather than worry about what terrible destruction might some day fall from the sky.

In the end, thankfully, war didn't come, the bomb shelters were never needed, and now they are mostly forgotten. My local post office has a fallout shelter sign, likely dating from the Kennedy era – capacity 55 people – and I asked one of the postal workers there if I could see the old shelter room. She had no idea what I was talking about. When I told her about the sign, she thought I meant a demonstrator had stuck a placard on the building.

Hopefully, those dark and paranoid days will never come again. But, if they do, the plans and proposals are still ready, if we need them.

Figure 12: Shelter Corridor^[Pa]

(Copyright Expired)

Works Cited

[An]: Anonymous, personal communication.

[ARF]: Evaluation of Deep Tunnel Shelters. Armour Research Foundation, 1958. CD-SR-58-55.

[Bl]: Blanchard, B. Wayne. “American Civil Defense 1945-1984: The Evolution of Programs and Policies.” National Emergency Training Center, 1985. http://www.orau.org/ptp/pdf/cdhistory.pdf

[Br]: Brode, H. L. “Nuclear Burst Phenomena Pertinent to Deep Underground Structures.” Protective Construction in a Nuclear Age: Proceedings of the Second Protective Construction Symposium. March 24-26, 1959. RAND Corporation, 1961.

[CBR]: Cathcart, R. B.; Badescu, Viorel; and Radhakrishnan, Ramesh. Macro-Engineers' Dreams. http://textbookrevolution.org/files/Cathcart-MacroEngineersDreams.pdf

[CGO]: Committee on Government Operations. Hearings on Civil Defense. April 30, May 1,2, 5-8, 1958. Government Printing Office, 1958.

[FCDA]: Annual Report of the Federal Civil Defense Administration for Fiscal Year 1958. US Government Printing Office, 1959. http://training.fema.gov/EMIweb/edu/docs/HistoricalInterest/FCDA%20-%201958%20-%20Annual%20Report%20for%201958.pdf

[FFL]: Fleming, Robert W., Frandsen, Alton D., and LTC LaFrenz, Robert L. “Stability of Nuclear Crater Slopes in Rock.” Symposium on Engineering with Nuclear Explosives. January 14-16, 1970. Atomic Energy Commission, 1970. CONF-700101. Vol. 2.

[Gh]: Ghamari-Tabrizi, Sharon. Worlds of Herman Kahn: The Intuitive Science of Nuclear War. Harvard University Press, 2005.

[K]: Kahn, Herman. On Thermonuclear War. Princeton University Press, 1960.

[K2]: Kahn, Herman. “Why Go Deep Underground?” Protective Construction in a Nuclear Age: Proceedings of the Second Protective Construction Symposium. March 24-26, 1959. RAND Corporation, 1961.

[Ka]: Kaplan, Fred. The Wizards of Armageddon. Simon and Schuster, 1983.

[LoC]: Library of Congress Prints and Photographs Online Catalog. “Interview with Herman Kahn, Author of On Escalation.” Retrieved July 23 2013. http://www.loc.gov/pictures/item/2004666287/

[Mi]: Mitchell, John G. “The Man Who Would Dam the Amazon.” Audobon, Vol. 81, March 1979, pp. 64-81.

[NAS]: Effects of Nuclear Earth-Penetrator and Other Weapons. National Academies Press, 2005. http://www.nap.edu/catalog.php?record_id=11282

[NWA]: “The Minuteman III ICBM.” Nuclear Weapons Archive. Accessed August 28 2013. http://nuclearweaponarchive.org/Usa/Weapons/Mmiii.html

[NY]: New Yorker, March 5 1960, p. 134.

[NYT]: “Guy Panero Dead; Engineer was 69.” New York Times, May 15 1961, p. 31.

[NYT2]: “Swiss Ready to Face Armageddon, in Comfort.” New York Times, November 27 1987. http://www.nytimes.com/1987/11/27/world/swiss-ready-to-face-armageddon-in-comfort.html?pagewanted=print&src=pm

[Pa]: Manhattan Shelter Study. Guy B. Panero Engineers, 1958.

[Pa2]: Report on Underground Installations – Summary. Guy B. Panero Engineers, 1948. W-49-129-Eng-59.

[Pa3]: Panero, Robert B. “A South American 'Great Lakes' System.” Hudson Institute, 1967.

[RAND]: Report on a Study of Non-Military Defense. RAND Corporation, 1958. R-322-RC. http://www.rand.org/pubs/reports/2008/R322.pdf

[Se]: Seyfried, Paul, personal communication.

Copyright Note: No record of copyright renewal was found for the Manhattan Shelter Study in a search of the US copyright registration database, nor could the original rights-holders be located. If you are the rights-holder or their agent you can contact me at MarkAtAtomicSkies -at- GMail -dot- com.

With Special Thanks to my Pre-Reader, B. Bennet