Our goal there, in my view, is to work and lean strongly on China to put as much pressure. China is one of the few major countries in the world that has significant support for North Korea, and I think we got to do everything we can to put pressure on China. I worry very much about an isolated, paranoid country with atomic bombs.

The Affordable Care Act has clearly, as Secretary Clinton made the point, done a lot of good things, but, what it has not done is dealt with the fact we have 29 million people today who have zero health insurance, we have even more who are underinsured with large deductibles and copayments and prescription drug prices are off the wall.

It costs a hell of a lot more money to put somebody in jail than send them to the University of Virginia.

What we have got to do immediately is to say that racism and xenophobia is totally unacceptable and we will stand with the 1 percent of our population who are Muslims, for undocumented people in this country. Absolutely, we will stand.

I don't believe in trashing my opponents. I've never run a negative ad in my life. I believe in talking about issues, sometimes fighting for the media to talk about the issues, but that's what I do, and the people will decide.

The good news is that we've seen in recent years significant reductions in the cost of solar panels and wind production. We know how significant an impact we can have by moving towards energy efficiency and transforming our transportation system. So we know what has to be done. We have to develop the political will to do it, and, as president, this would be an issue of huge concern to me.

The U.S. constitution is an extraordinary document. In my view, it should not be amended often.