Why does the UK have nuclear weapons? or France?

While the nuclear powers, especially the United States, Britain and France, express great concern about Iran developing a nuclear weapon and while they issue threats of sanctions and even darker measures, an obvious question is being overlooked. Why exactly do Great Britain and France have nuclear weapons?

With nuclear neighbours to the north and east, wars being fought by nuclear-armed nations on its eastern and western borders, and its access to the sea prowled by the warships of a hostile, nuclear-equipped power, if any nation can justify a nuclear arsenal, it's Iran. Great Britain and France, on the other hand, are surrounded by friends and the only nuclear neighbours they have are each other.

Nonetheless, Iran claims it isn't developing a weapon and the United States' intelligence agencies concur. If it was, it would be in violation of the Nuclear Non-proliferation Treaty which it has signed. But then all signatories to the treaty are committed to "pursue negotiations in good faith on effective measures relating to cessation of the nuclear arms race at an early date and to nuclear disarmament, and on a treaty on general and complete disarmament under strict and effective international control." We see sparse evidence that Britain and France, or the United States for that matter, are acting "in good faith" to achieve "complete disarmament."

So what's stopping Britain and France from doing their duty by setting an example? Why not adhere to the spirit of the treaty themselves and disarm their nuclear arsenals? We're waiting, Messrs. Brown and Sarkozy.

Someone might go further and ask why anyone has these insane weapons. Good question. One the nuclear powers might be asking themselves, and each other, even while they self-righteously condemn Iran.