In defense of Duck and Cover

Now that the Cold War is over, people will occasionally look back at the horrifying situation — two opposing superpowers threatening the world with annihilation ­— view the threat as over, and laugh at some of the things people said and did back then. Now I know that this is partly because laughter is the only way to deal with such a nightmare, but some of the specifics they choose are just wrong. Take for example this John Oliver clip about nuclear weapons:
 He argues convincingly that there is still a threat, and that we need to do something about it. But he opens by mocking "Duck and Cover", which is actually misguided.

"Duck and Cover" was part of a broader civil defense program that tried to prepare Americans for nuclear war: fallout shelters, iodine tablets, and yes, public education. Oddly, the whole idea of civil defense was controversial: if a nuclear war will destroy all of modern technological civilization, civil defense measures don't actually make people much safer, but they might give people the impression that nuclear war would be survivable, and maybe even make the voting public less reluctant to pay for implementing it.

All that said, I want to talk specifically about "Duck and Cover". The basic message is just that: if you see a flash, get down and cover all your exposed skin as best you can.

I should point out up front that this was in 1951, before the hydrogen bomb or ICBMs; the threat they were worried about was Nagasaki-like bombings: atomic weapons large enough to destroy cities dropped from bombers. And in 1951 the world supply of such bombs was actually rather modest. So a nuclear war would have meant destruction of one or a few cities — mostly the city center areas — but not the complete destruction of a nation or nuclear winter.

So is this advice useful for someone in or near a city where a tens-of-kilotons nuclear weapon goes off? Yes, actually. For that matter, this sort of public relations campaign would have helped a situation I have a family link to, the Halifax explosion. This happened during World War I when a munitions ship caught fire and blew up in the largest man-made explosion before the nuclear age. My great-aunt Florence was working as a nurse at the time, and her most vivid memory was of the buckets of eyeballs in the clinic at the end of the day: people saw the flash and turned to look out their windows, which blew in when the blast wave arrived. An awful lot of people lost their eyes who would not have if they had instead reacted by ducking down. Of course, there was no reason for such a civil defense program back then; it was not until we began systematically building weapons to destroy a city at a time that it was sensible.

A nuclear blast is of course not quite the same as the Halifax explosion; specifically, it has dangers that that explosion did not. The light from a nuclear explosion has a characteristic double flash. Initially the few meters around the device become incredibly bright. But within a millisecond or so the air nearby becomes plasma, and opaque, so the brightness drops by a factor of ten. The fireball expands rapidly, of course, and the light begins to shine out after perhaps a third of a second, ultimately releasing about half the weapon's energy as thermal radiation. That gap between the initial flash and the release of the bulk of the thermal energy is maybe just long enough to cover exposed skin, and definitely to at least look away. And covering the exposed skin can make a huge difference. The photo to the right shows a man who was in Nagasaki when the bomb went off: his exposed arms were badly burned, but his relatively light vest protected his torso. So covering up could save you from severe flash burns, even if all the warning you had was the initial flash. Not much time to think about it, so it would need to be drilled into you; hence "Duck and Cover" and drills.

John Oliver then follows up with footage from the 1983 film The Day After, which he argues is more realistic. Ironically. the scene he shows — in which Danny's father tries to rescue him — illustrates what I mean. Danny is blinded by the (second) flash, which covering himself would have saved him from. Much of the movie is about the aftermath (as its title suggests) when hospital and other social support systems are completely overloaded by the scale of the destruction. The even more horrifying Threads (from 1984) expands upon this theme, depicting the appalling conditions of Britain even years after such an exchange.

The difference between these films and "Duck and Cover" is that these are from the early 80s, when the superpowers had tens of thousands of thermonuclear warheads pointed at each other (actually while making Threads one of the British civil defense folks they consulted mentioned that they had been warned to prepare for American nuclear warheads launched to deny the Soviets the use of Britain as an invasion launching point). By this point, even the most optimistic models were based on the idea of "killing a nation" by destroying all major cities, governmental organization, and industrial productivity. Since many of these warheads were on ICBMs or well-hidden nuclear submarines, a more realistic picture has both superpowers being destroyed as nations, along with anyone else who seemed like a plausible target (anyone in NATO or the Warsaw Pact for sure). This is enough to destroy civilization as we know it.

Nuclear war meant something profoundly different in the 80s than it did in the 50s, so laughing at the 50s' "mix of optimism and pessimism" is missing the point. The nightmare of annihilation is something we planned for, we paid for, and we almost made happen, in that "Golden Age" some politicians want to return to.