I think there are worse things than war. For example, injustice.

When I went to war, I did not go making geopolitical calculations. I went to war with a lust.

By the 20th century, war ceased to be an encounter between two armies. It became an encounter between two societies, because a factory worker producing a gun or a bomb is as deadly as a pilot.

The British bombed German cities [during World War II] to keep the workers awake at night. So instead of dropping one bomb, we sent a thousand planes and, yes, we took out the factory sometimes, but we also took out the city. It reached the point where we wanted more efficient ways to destroy a city. The result was nuclear weapons.

Constraint theory argues a number of things. First, that the impossible has to be identified. Second, that the actor is then constrained by circumstances to act a certain way. For example, should we invade ISIS? Can we invade ISIS? What would it take to invade ISIS? Once you ask that question you discover the price of that option and then you take a look at American politics and see that the country is probably not prepared to invest the 2 to 3 million people that it would take to defeat ISIS and the insurgency afterwards. All right, so that's not going to happen.

The most horrible sort of war is civil war.

What is revolutionary today is that we're using precision-guided munitions. And instead of building individual weapons, we are building an industry and a philosophy, the culture of precision. You saw Desert Storm. Precision works.