Fortunately, President Kennedy and Robert Kennedy disagreed with the estimate and chose a course of action less ambitious and aggressive than recommended by their advisers.

There's a long record here of being wrong. There's a good reason for it. There are probably multiple reasons. Certainly proliferation is a hard thing to track, particularly in countries that deny easy and free access and don't have free and open societies.

I am worried because I'm hearing some of the same signals about Iran and its nuclear program that were heard as the Bush administration made its case for the war in Iraq. 'It's déjà vu all over again.

I had innumerable analysts who came to me in apology that the world that we were finding was not the world that they had thought existed and that they had estimated. Reality on the ground differed in advance.

Fortunately, President Kennedy and Robert Kennedy disagreed with the estimate and chose a course of action less ambitious and aggressive than recommended by their advisers.

And you know, almost in a perverse way, I wish it had been undue influence because we know how to correct that. We get rid of the people who, in fact, were exercising that.

Let me begin by saying, we were almost all wrong, and I certainly include myself here.