I don't think that anyone seriously fears that the world can be blown to pieces all together. But what one can fear and rightly so are regional things, like in the Middle East, India, Pakistan, the Korean Peninsula, borders in Africa, etc.
Hans BlixOn big issues like war in Iraq, but in many other issues they simply must be multilateral. There's no other way around. You have the instances like the global warming convention, the Kyoto protocol, when the U.S. went its own way.
Hans BlixIraq did not spontaneously opt for disarmament. They did it as part of a ceasefire, so they were forced to do it, otherwise the war might have gone on. So the motivation has been very different.
Hans BlixThe South Africans decided that they would like to prove to the world they did not have any nuclear weapons and their decision was not doubted because it was the end of the Cold War, it was also the end of apartheid.
Hans Blix