Unless we free ourselves from a dependence on these fossil fuels... we are condemning future generations to global catastrophe

I believe in keeping guns out of our inner cities, and that our leaders must say so in the face of the gun manufacturer's lobby.

The truth is that, in trying to get at terrorists who are in countries that either are unwilling or unable to capture those terrorists or disable them themselves, there are a lot of situations where the use of a drone is going to result in much fewer civilian casualties and much less collateral damage than if I send in a battalion of marines.

Cutting our education budget, that's not a smart choice. That will not help America compete with China.

I think what is true is that there's been an underlying division in the United States. Some of it has to do with the fact that economic growth and recovery tends to be stronger in the cities and in urban areas. In some rural areas, particularly those that were reliant on manufacturing, there has been weaker growth, stagnation, people feeling as if their children won't do as well as they will.

America must always lead on the world stage. If we don't, no one else will. The military that you have joined is, and always will be, the backbone of that leadership. But U.S. military action cannot be the only - or even primary - component of our leadership in every instance. Just because we have the best hammer does not mean that every problem is a nail.

As you get older, your mind gets a little more set. And it needs the poking and prodding and breaking through of stereotypes that I think young people provide.