There are folks who will equivocate. They'll say, 'You know, I'm not a scientist.' Well, I'm not either. But the best scientists in the world know that climate change is happening.

I've got certain responsibilities that I have to carry out in a very specific institution and in a specific moment in time.

[About his marijuana use] I did. It's not something that I'm proud of. It was a mistake as a young man, but you know? I mean not going to -- I never understood that line. The point was to inhale. That was the point.

I think that the Democrats can be successful nationally in the future if we are able to capture some of the complexity of people's lives right now.

I think what will happen with Donald Trump is there are going to be certain elements of his temperament that will not serve him well unless he recognizes them and corrects them.

America is not - and never will be - at war with Islam. We will, however, relentlessly confront violent extremists.

No single nation should pick and choose which nations holds nuclear weapons. And that's why I strongly reaffirmed America's commitment to seek a world in which no nations hold nuclear weapons.