FT.com / Comment & analysis By declaring that "the war on terrorism will not be won on the defensive", the president gave notice that the US intended to discard the conventions that have governed relations between nation states for more than half a century. Washington wants to impose new limits on the sovereignty of adversaries, real and potential. It is reinterpreting the meaning of self-defence. In short, America's war against terrorism is not simply a matter of hunting down al-Qaeda or, even, confronting today's rogue states. The changes in the geopolitical game proposed by Mr Bush are at once profound and troubling.

At the heart of all this is the belief that US security can no longer rely on the familiar cold war doctrines of containment and deterrence - an approach that until September 11 had survived the fall of the Berlin Wall. Mr Bush said that deterrence - the threat of massive retaliation - did not work against shadowy terrorists. Containment was not an option with "unbalanced dictators" capable of delivering weapons of mass destruction on ballistic missiles.