Power... Military success is not sufficient to win: economic development, institution-building and the rule of law, promoting internal reconciliation, good governance, providing basic services to the people, training and equipping indigenous military and police forces, strategic communications, and more of these, along with security, are essential ingredients for long-term success.

Well, I've ruffled a few feathers at all the institutions I've led. But I think that's part of leadership.

I think Donald Trump has gotten China's attention to a degree that his predecessors have not that this is a very serious matter for the United States.

Well, what I've said is that the war in Iraq will always be clouded by how it began, which was a wrong premise, that there were in fact no weapons of nuclear - weapons of mass destruction.

My one concern is that Hu Jintao may overestimate how much power China has in Pyongyang. They have - they do have influence, and they do have companies, and they do have economic relationships that could make life much more difficult in the north. Their balancing act is, "How much worse can we make it in the north without creating that which scares us more than anything, which is a collapse in the north." And then what happens to all those nuclear weapons. So they're going to work very hard to avoid that.

I had no difficulty as Secretary of Defense moving from the Bush administration to the Obama administration.

I've been very sensitive for a long time to the repeated pattern, during economic hard times or after a war, of the United States' essentially unilaterally disarming.