Why do Britain and France have nukes?

A lot of people continue to ask me if I could explain how and why British and French nuclear submarines collided in the Atlantic last week. What are the chances of such a thing happening? And what interesting questions does it raise — like why do Britain and France even have nukes anymore?

First, this is not as unlikely an accident as you might think. These subs tend to pass through regions of the Atlantic where the Gulf Stream is strongest and they’re, therefore, hardest to detect.

Second, both countries are extremely secretive about the positions of their submarines. On board, only the captain and senior officers generally know with much precision where they are. France will finally rejoin NATO’s military structures this April, but that’s unlikely to make them any more forthcoming about the nuclear submarine force.

Finally, stealth sonar technology works. Neither of the submarines would have detected the other–even at close quarters. These are the main reasons why this collision was merely really, really, really unlikely rather than virtually impossible.

Now for the much more interesting question: Why do Britain and France continue to maintain a nuclear deterrent? The two countries now have just four nuclear strike submarines each. The UK abandoned its airborne capability in 1998 and is now dependent on these subs. France still has an airborne capability, but this is steadily reducing, and its submarines now carry 80 percent of its nuclear weapons.

Yet, France has maintained its total nuclear weapons stockpile at around 400. Britain has probably halved its stockpile from 350 to about 170 since the end of the Cold War — a level that is now smaller than Israel’s estimated force and roughly equal to those of India and Pakistan. But the British government announced in March 2007 that it would spend 20 billion pounds to replace its nuclear sub force when it becomes obsolete a decade from now.

So this collision did not amount to a serious accident, but it may prod some to question why France and Britain would spend billions to maintain a nuclear weapons deterrent, a symbol of prestige more than a security guarantee, in the midst of a global recession.

I’ll leave that question for French and British officials to answer.

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