It's clear the relationship between China and North Korea has hardly ever been worse. Kim Jong-un has never been to Beijing in his leadership. The Chinese press are saying some amazingly negative things about the north, and about Kim Jong-un. So - so they are weighing in, and they are bringing greater pressure. Whether it will be enough I think remains to be seen.

No policy has proved more successful in making friends for the United States, during the cold war and since, than educating students from abroad at our colleges and universities.

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 fired a lot of senior people myself and I think the key, when you feel compelled to remove a senior official, is essentially to have all your ducks in a row at the beginning. Have everybody understand what the rationale was.

On the foreign policy side, there's the risk of being too spontaneous and too disruptive where you end up doing more harm than damage. And figuring out that balance is where having strong people around you matters.

I've seen, all too often in my career, people coming in to lead agencies and organizations and trying to impose change from the top down. Never works. You never have enough time.

I think in the policies that have been followed since the president Donald Trump came into office, there really hasn't been any slack cut for the Russians. And I think one of the things that has surprised people has been that the relationship between the United States and Russia has in fact deteriorated since the election.