I think if terrorists had nuclear materials and found people to put a bomb together - both of which are possible - we would already have seen a nuclear explosion. But we have literally thousands of people around the world working their tails off and making a lot of sacrifices to contain nuclear materials. I particularly would like to compliment the Russians on this. In times of great economic distress, many of them could have made an awful lot of money if they had sold their expertise.

I don't think that within a certain amount of time we can get rid of all nuclear weapons. But I do believe that, step by step, we could get others to join us. I call it going up the mountain. We can get to the top eventually, but we have to get to base camp first. Right now, we are in the valley. So we have a long way to go, but maybe our children or our grandchildren will see the top of the mountain.

Leadership must be established from the top down.

It's very hard for Europe, the US and Russia to have much influence on the growing problems elsewhere in the world unless we have our own backyard in a more stable and cooperative atmosphere.

We are in a race between cooperation and catastrophe, and the threat is outrunning our response.

If you think you're a leader, and you look over your shoulder and there ain't nobody following you, man, you're just takin' a walk.

We need a dialogue with the Iranians, and it is going to take both carrots and sticks. We employed very tough economic sanctions, and they are having an effect. But we also have to give the Iranians an idea of what the economic and cooperative possibilities would be if they did give up their quest for a nuclear weapon.