But the truth of the matter is, we're an open society, we want to remain an open society, and there will continue to be vulnerability. That's why we have to meet the threats when they are not yet taking place on our territory and on our soil.

I think America is still a bright, shining city on the hill - not because we're perfect but because we struggle in our imperfections every day.

Once a month I play with a chamber music quartet. I play almost no solo music anymore because I so enjoy the interaction. The members of my quartet have become some of my best friends and so I really enjoy it now in ways that I didn't before.

The United States government does not authorise or condone torture of detainees. Torture, and conspiracy to commit torture, are crimes under US law, wherever they may occur in the world.

Arnold Rampersad is a really good person. A really good person. As a matter of fact, he came to Stanford when I was Provost.

I certainly have no regrets about overthrowing Saddam Hussein. I'd do it again. And, yes, there are a lot of things that I think we'd all do differently. Maybe we made some erroneous assumptions about the fabric of the society in Iraq and about the solidity of some of the institutions. And yes, there are a lot of things I would do differently. I'd probably work to rebuild Iraq from the outside in, rather than concentrating so much on Baghdad, for instance.

I know that people look at my life and ask, "How can I achieve some of those things?" So, I suppose in that sense, yes, I'm a role model. But I try to think of myself more as a mentor, as somebody who I hope young people feel comfortable approaching or writing to.