We live in a fantastically wealthy country. We don't have to worry about food. We don't have to worry about clothing. We don't have to worry about our safety. It's very easy for me to be an environmentalist. It's very easy for me to care about making sure that we protect the forests and the whales, and all that stuff.

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.

There is too large a divergence at the moment in the interests and values of the world's most powerful states.

I think the best way to control a population is to urbanize and to educate women. We have seen historically in many, many countries that once women are educated and have opportunities, and that happens when they live in cities and once they improve their economies, they no longer want to have eight kids. They want to have one or two or maybe three. And that is much more sustainable for them because they have other opportunities.

In the nearer term, the likeliest source of risk is a conflict between China and the U.S. These are now the two largest economies in the world, and the combination of their economic interdependence, the sharp differences in their political and economic values, and the growing divergence in their interests makes this relationship potentially dangerous for everyone who might be affected by it - which means pretty much everyone.

I don't see a coherent global order anywhere on the horizon.

International institutions like the Security Council, the General Assembly, the G20, the BRICs, the IMF, etc., continue to be little more than an extension of the (increasingly conflicting) values and interests of member states.