And I argued with that intelligence estimate and I think it is a responsibility of policymakers to use their best judgment on the basis of the intelligence they've received.

Putin has a lot at stake here and restoring the relationship with the United States, and there are already signs as Sandy mentioned that he's moving in the right direction to begin to ascertain that their trade with Iran is not used for the production of nuclear weapons.

Intelligence is not a science.

I wouldn't even know - and I spent three years in the CIA - I wouldn't even know how you'd start a covert action program in a place like Iran. It would be extraordinarily difficult.

We went into Iraq because Iraq posed a threat to the stability of the region and was engaged in the process of trying to develop weapons of mass destruction and had links to terrorists.

There's clearly something to be said for success and following through on your commitments.

It took us 50 months in Germany, post World War II to go from the end of the war to a national election.

The problem is that neither the M1 nor the M60 or indeed neither any tank, has sufficient ground pressure to drive a [bulldozer] blade into even marginally hard ground. They are not bulldozers, they are tanks, whether you are talking about the M1 or the M60's. So if you are going to dig in a tank, you need to have some kind of equipment.

Of course, China is a key to the North Korea if we're going to solve that riddle, but they could also be helpful on Iraq, which is why it's important that we maintain a constructive dialogue with China.

So, I think even in Saudi Arabia there is movement. And we have to remember that over the years they've stabilized the oil price and that is tremendously important for the economies of the world. I think we have no choice but to work with the government of Saudi Arabia.

Policymakers have to make judgments based on the best intelligence they get.

The Crown Prince has said he needs to broaden political participation in the governing of Saudi Arabia.