I've seen, all too often in my career, people coming in to lead agencies and organizations and trying to impose change from the top down. Never works. You never have enough time.

I had no difficulty as Secretary of Defense moving from the Bush administration to the Obama administration.

One of the toughest battles in intelligence is combating conventional wisdom.

In government, I'm a strong believer in the need for reform of government agencies and departments. They - they have gotten fat and sloppy, and they're not user friendly. They are inefficient. They cost too much.

I think in the policies that have been followed since the president Donald Trump came into office, there really hasn't been any slack cut for the Russians. And I think one of the things that has surprised people has been that the relationship between the United States and Russia has in fact deteriorated since the election.

I mean, when you get down to very low numbers of nuclear weapons, and you contemplate going to zero, how do you deal with the reality of that technology being available to almost any country that seeks to pursue it? And what conditions do you put in place?

There's a lot of books out there about how you lead change in business, but I've certainly not seen any... on how you do that in public institutions.