A low-carbon, clean energy economy can be an engine of growth for decades to come.

Let's face it, I like Stanford grads. I'd always hear about this campus, and everybody is riding bikes, and people hopping into fountains.

The United States has been a Pacific nation for over two centuries. That's not going to change.

I think it's very important to remember that so much of the work that gets done between countries is not done at the level of presidents, but is done within various agencies, whether it's law enforcement or economic ministries. And when they establish relationships and systems of communications and shared projects and shared visions, those structures continue even after any particular president is gone. It builds trust and understanding between countries that are critically important.

Constitution is a living document; no strict constructionism.

I think that what is always true when you run against an incumbent president is, is that you end up talking more about that president's record than your vision for the future, and I think that the Democrats do have to present a proactive agenda and vision for the country and not simply run against something if they're going to be successful.

We are not going to be able to rebuild Afghanistan into a Jeffersonian democracy.