Explosive material plus radioactive material equals dirty bomb.

You don't find people of integrity who operate in that zone.

We are seeing the most intense bargaining among big states that we have seen since the end of the Cold War, with war in the offing and no certainty about the outcome.

The North Koreans have every intention to lie, steal and cheat as much as they can get away with and as they have been doing for decades. But they would also say we've been cheating them through the whole process or acting in bad faith.

The danger is that a terrorist like Osama bin Laden who is very motivated ... gets a bomb out of a place like Russia. [Say] some crook steals it, he sells it to Osama bin Laden, Osama bin Laden brings it to Cleveland, or Boston, or L.A., and blows it up.

There is going to be lots of twists and turns here, and I think both the U.S. and Iraq will end up making some compromises, accommodations, as we get towards endgame.

They could bring the weapon today inside a cargo container that comes to one of our ports, and the technologies that we have deployed would have a low chance of finding it.

My bottom line is that if the U.S. government just stands on the autopilot, just on the current trim line ... I think that it is more likely than not that we will see a nuclear bomb exploding in one of our cities in less than a decade.

That means no new national production of highly enriched uranium from which a bomb could be made, and that's the issue over Iran.