The government, of course, won't say. But Hans Kristensen of the Federation of American Scientists and Robert Norris of the Natural Resources Defense Council tried to figure it out anyway. Here's a map of all the likely locations:

       

The mother lode seems to be in Bangor, Washington, where 2,300 weapons are housed, although about half of them are deployed on nuclear submarines lurking around the Pacific Ocean at any given time. The follow-up discussion by Kristensen at FAS's blog makes for fascinating reading. Among other things, he notes there's no evidence that there are nuclear submarines roaming the waters of the Indian Ocean, prepared to strike, say, Iran. In case anyone was wondering.

The United States is dismantling fewer warheads at a slower pace today than it did in the 1990s, and still has roughly 10,000 nuclear weapons intact, which may seem a bit excessive to some. The current plan is to whittle its arsenal down to 6,000 by 2012—still excessive, but better. We'll see how that goes. Keir Leiber and Daryl Press have argued that the United States may be approaching a point of nuclear dominance, where it could, potentially, strike Russia or China and disable their missiles before either country had the chance to retaliate. It's unclear whether the United States would actually try to expand its nuclear capacity to try to reach that point, although the Bush administration sure acts like that's the goal sometimes.

Meanwhile, Jeffrey Lewis takes stock of the debate going on in Britain right now over whether the country still needs a nuclear deterrent in this day and age. Lewis says the debate's a bit surreal because "the UK’s nuclear weapons are irrelevant: they don’t deter anyone, confer any status or, frankly, threaten anyone." But the government still wants them. The United States may also have an interest in keeping Britain's arsenal up and running, since a disarmed Britain would be less likely to maintain its role as a key ally during various nuclear-weapons debates within NATO. I mean, not that the United States would try to apply any undue pressure here or anything...