To the extent that our political dialogue is such where everything is under suspicion, everybody is corrupt and everybody is doing things for partisan reasons, and all of our institutions are full of malevolent actors - if that's the storyline that's being put out there by whatever party is out of power, then when a foreign government introduces that same argument with facts that are made up, voters who have been listening to that stuff for years, who have been getting that stuff every day from talk radio or other venues, they're going to believe it.

And if we walk away now, if we simply retreat into our respective corners, we will never be able to come together and solve challenges like health care, or education, or the need to find good jobs for every American.

We, the people, still believe that our obligations as Americans are not just to ourselves, but to all posterity.

The other reason might be that you want to talk to voters when you've got seven primaries in seven days. Understand what's happened in this race - where we campaign actively in a state, and voters have the chance to see me directly, they check under the hood, and they kick the tires, when we don't have as much time.

To avoid being mistaken for a sellout, I chose my friends carefully. The more politically active black students. The foreign students. The Chicanos. The Marxist professors and structural feminists and punk-rock performance poets.

I think I did in the sense that there's a whole generation coming up behind us that was engaged, inspired, worked for change during the course of my presidency, saw what was possible. And that generation, it's coming.

It's probably a prerequisite for the job, or at least you have to have enough craziness to think that you can do the job. I think that [Donald Trump] has not spent a lot of time sweating the details of, you know, all the policies.