I flew on Air Force Two for eight years, and now I have to take off my shoes to get on an aeroplane.

I think the ethical standards established in this White House have been the highest in the history of the White House.

In physics there's the old law for every action there's a equal amount of reaction. Sometimes that's true in politics. If somebody's out there making nonsensical statements, but wielding power behind them a lot of people say, "Well, I need to react to that." Another reason for the increased prominence of the climate-change issue is the Paris Agreement itself. It's not a small thing when just about every nation in the entire world comes together and makes an historic agreement like this. It's a big deal. And the old cliché "The train is leaving the station" kind of applies.

I don't have the illusion that there's any position or role in the world with as much potential for bringing about change as that of president of the United States.

The good news is, we have everything we need now to respond to the challenge of global warming. We have all the technologies we need, more are being developed.... But we should not wait, we cannot wait, we must not wait.

We sometimes emphasize the danger in a crisis without focusing on the opportunities that are there. We should feel a great sense of urgency because it is the most dangerous crisis we have ever faced, by far. But it also provides us with opportunities to do a lot of things we ought to be doing for other reasons anyway. And to solve this crisis we can develop a shared sense of moral purpose.

I think that more diversity is a good thing, and fresh points of view articulated by people who are committed to excellence in journalism is a beneficial change in the American media landscape.