You Might Want to Know: How do we keep Unauthorized Persons from setting off our nuclear weapons?
You Might Want to Know: How do we keep Unauthorized Persons from setting off our nuclear weapons?
Today, the U.S. has a stockpile of over three thousand nuclear weapons. Most have many times more explosive power than the bomb that destroyed Hiroshima. In the 80’s, we had twenty-eight thousand nuclear weapons in our stockpile, so we’ve come down some. Three thousand is still a lot. What if an Unauthorized Person got his or her hands on one of those nuclear weapons and wanted to set it off? How do we think we can keep that from happening?
First of all, we try to keep the weapons out of the hands of Unauthorized Persons, of course. If we are storing weapons, we put them in facilities we try to make secure and don’t let everyone know where the facilities are. We hope no Unauthorized Person finds out where we’ve put them and, if they do, that the facilities are secure enough to keep an Unauthorized Person from getting one. A lot of us do know where we’ve stored some of them, though. We are, of course, Unauthorized Persons.
We also know, don’t we?, that where there’s a will, there’s often a way.
What about the weapons that have been deployed? “Deployed” means they are out there with our armed forces. Some are in places that are pretty secure—like in underground silos and nuclear submarines. But starting in the 50’s, we sent over to Western Europe, mostly Germany, hundreds of “tactical” nuclear weapons. Tactical nuclear weapons are the ones lower in yield than our big “strategic” bombs, though still many many times more powerful than the biggest conventional weapons we have. The yield of the bomb that destroyed Hiroshima is today within the range of what we consider “tactical.” It was “strategic” then. Today bombs with the yield of the Hiroshima bomb are small enough in size and weight to be maneuvered by soldiers in the field.
Or by Unauthorized Persons.
You can see how tactical weapons with soldiers in the field could more easily fall into the hands of an Unauthorized Person.
We now have bombs, like our B61, that can be set to different yields, called “dial-a-yield” weapons. The B61 can be set to yield the equivalent of three hundred tons of TNT, or the equivalent of three hundred fifty thousand tons. That’s quite a range, isn’t it? Just by looking at at a B61, you wouldn’t be able to tell what it was set at. In any case the B61 would weigh only about seven hundred pounds. You couldn’t carry it by yourself, but it wouldn’t be that hard to carry off a B61. Especially if it were on one of those wheeled carriers you see in pictures.
Tactical nuclear weapons are supposed to do things like collapse mountain passes or blast massive holes in front of advancing tanks or kill great big bunches of soldiers if they happen to be in great big bunches. In the 50’s, 60’s and 70’s, we stationed hundreds of these weapons in Western Europe. We planned to use them on the Soviets when they poured across the border in their tanks, as we were just sure they would if it weren’t for us and our nuclear weapons.
We also have stationed more powerful “strategic” nuclear bombs in the countries that have allowed us to put them there--in England, Italy, Turkey, and South Korea, for example. Not in Japan. Nuclear weapons aren’t welcome there.
Nuclear weapons stationed in foreign countries could more easily fall into unauthorized hands, of course. But as far as I know, no Unauthorized Person has yet gotten hold of one of ours, here or anywhere else.
Let’s say an Unauthorized Person or group did get hold of one of our nuclear bombs, tactical or strategic or dial-a-yield. Let’s say they saw themselves as at war with us or were just crazy with hate, even suicidal. What would prevent the Unauthorized Person or group from setting the weapon off? Anything?
In the beginning, what could have prevented them was how complicated it was to set one off. We kept the fissile fuel out of the bomb and if you wanted to produce a nuclear explosion, you’d have to know how to put the fissile fuel into the device and get the detonators on the conventional explosives hooked up.
Starting in late 50’s, though, as we began to send all those tactical nuclear weapons to Europe, we had begun to develop something called Permissive Action Links for the weapons. PALS were supposed to make it harder to set off the weapons. The first PALs weren’t much more than the combination locks we had on our school lockers, but that was something.
In 1962, President Kennedy ordered PALs to be installed on all the tactical nuclear weapons President Eisenhower had sent over to Europe for NATO. He’d sent over a bunch. Hundreds.
The military leaders in the Army didn’t like the idea of PALS. They worried that in a crunch the PALs might slow them down. They were ready to run the risk of an Unauthorized Person getting hold of one. To protect the tactical nuclear weapons from local protesters, they trained Quick Reaction Forces. In Germany especially, the local protesters got to be a big worry.
Along the way, we had begun to produce “sealed pits” for our missiles. Sealed pits had the fissile fuel and tampers and reflectors and initiators already in a “physics package” and the conventional explosives and detonators already in place around the pit. No assembly required. If you got hold of a sealed pit, all you would have to do to produce a nuclear explosion would be to set off the conventional explosives inside it. To do that, all you would have to do would be to send the electrical charges to the detonators. You might be able to do that with a car battery.
Our newer weapons had fewer detonators too. The Nagasaki bomb had more than thirty. Our newer bombs needed only two.
The Minuteman Intercontinental Ballistic Missiles that we deployed in underground silos in the U.S. in the 60’s and the Submarine Launched Ballistic Missiles we had in our submarines were a lot less likely to fall into the hands of Unauthorized Persons. Just how are you supposed to steal a warhead from an underground silo or a submarine?
There you might worry about someone in a Launch Control Center going off the deep end. We addressed this in the Minuteman Launch Control Centers by requiring launch control officers to receive and enter codes before a missile could be launched and by requiring two launch control officers to turn their launch keys at just the same time. Now you’d have to have two people going off the deep end before there could be a launch that was unauthorized.
In 1974, twelve years after JFK had given the order to fit all our tactical nuclear weapons with PALS, Secretary of Defense James Schlesinger discovered that many weapons still hadn’t been fitted with them. Our army, it turned out, was foot-dragging. Secretary Schlesinger ordered them to step it up. It took another two years, but we did get there. I think. Can’t say for sure. We may need to check to be sure.
PALs kept being improved and made harder to bypass. But on some of our nuclear weapons the combination locks didn’t get replaced with the newer PALS until 1987, two years before the end of the Cold War.
Since 2004, we’ve had for PALs had a nifty new electronic Code Management System, developed by Sandia Laboratories. These PALs are buried deep inside the nuclear devices. It wouldn’t be at all easy now to bypass the ones we’ve installed, in, for example, our B-61 bomb (yield up to the equivalent of 340,000 tons of TNT, twenty-two times Hiroshima). That’s good because we still have some B-61s deployed in foreign countries, at our Incirlik Air Base in Turkey, for example. And in Europe. And South Korea.
We’ve been told that today the new PALs have been installed on all of our nuclear weapons, except the ones in our submarines. That should help us sleep a little better, I suppose. It improves our chances that our nuclear weapons, at least, will be set off only by Authorized Persons.
Next: What’s the difference between a “counterforce” and a “countervalue” attack with nuclear weapons?