Strong states and blocs of strong states are the only source of power and legitimacy capable of driving an international agenda in today's world.

Academics were not a challenge when I was fifteen in college. The challenge was figuring out how to fit in socially.

I think graffiti is part of Berlin culture. You think about what the Berlin wall meant and how visible that was in everyone's life. How it was a part of their very identity.

Berlin is still a very edgy place, a very cosmopolitan place. It's a place where completely different ideas and cultures come together and clash in a very warm way. In a very warm-hearted way. It's a very young city. It's a vibrant city. It's an exciting city. It's a city that's also scarred by history. I think that's to be celebrated and graffiti is to be celebrated. Graffiti in Berlin is very different than when they spray something on the wall dividing the west bank and Israel. And should be treated as such in Berlin.

An emerging market is a country where politics matters at least as much as economics to the market.

The United States is not longer going to be the world's policemen and our days of determining you're in or you're out around the world no matter what the level of direct American interest or connection are going to be very limited. Increasingly, Africa will be doing that.

Climate is a global issue. Coal is still the energy that is being used more than anything else to make electricity. The United States is using less as we're turning more to gas. But, around the world, that's what they're using.