There's a strong nativist tradition - saying, "we have to protect ourselves" - that comes from the founding of the country. If you read Benjamin Franklin, who was one of the leading figures of the Enlightenment in the United States and the most distinguished representative of the movement here, he actually advised that the newly founded republic should block Germans and Swedes because they were too "swarthy" - dark.

You know, we have little bits of understanding, glimpses, a little bit of light here and there, but there's a tremendous amount of darkness, which is a challenge. I think life would be pretty boring if we understood everything. It's better if we don't understand anything and know that we don't, that's the important part.

In fact, it's doing it all over the world. Obama, first of all, is running the biggest terrorist operation that exists, maybe in history. The drone assassination campaigns, which are just part of it. All of these operations, they are terror operations.

Plainly, such an approach does not exclude other ways of trying to comprehend the world. Someone committed to it (as I am) can consistently believe (as I do) that we learn much more of human interest about how people think and feel and act by reading novels or studying history than from all of naturalistic psychology, and perhaps always will; similarly, the arts may offer appreciation of the heavens to which astrophysics cannot aspire.

Academics are not necessarily nice people.

On humanitarian intervention in general, I guess my view is not unlike the view that was attributed to Gandhi, accurately or not, when he was supposedly asked what he thought about western civilization. He is supposed to have said that he thought it would be a good idea. Similarly, humanitarian intervention would be a good idea, in principle.

The US reasserted control over Nicaragua in 1990. Since then, the country has experienced a steep decline. It's now the second poorest country in the hemisphere.