I've worked for four presidents, and I've concluded that almost nothing is inevitable. History is to a significant extent the result of the interaction of personalities and ideas. And so I don't believe war between the U.S. and China is in any way inevitable, and it's well within the province of diplomacy and statecraft to avoid it.

I've worked for four presidents, and I've concluded that almost nothing is inevitable. History is to a significant extent the result of the interaction of personalities and ideas. And so I don't believe war between the U.S. and China is in any way inevitable, and it's well within the province of diplomacy and statecraft to avoid it.

If the president Donald Trump had connected the Jerusalem question to some other positions, linking it to Israeli and Palestinian behavior or putting the Jerusalem statement in a larger context of U.S. policy, it could have potentially advanced the peace process. But I don't see how singling it out might help.

The reason I called the president Donald Trump a disrupter is that he came into office 70 years after World War II, 25-plus years after the end of the Cold War. Like any president, he didn't come into office with a blank slate - he entered with an enormous inheritance of relationships with institutions, policies and the like. And in my view he is much too quick to pull the U.S. out of various institutions and various agreements, and he's been much too quick to question the value of allies and alliances.

I think it was going to be hard to work with Russians on Syria. There is some potential overlap between the U.S. and Russia in that the Russians don't want to see the Syria situation unravel to a point where they have to escalate their own involvement. But at the moment, I don't see the U.S. and Russia on the same page in Syria. Russia seems much more interested in consolidating government control over liberated areas. It seems to me that the U.S. and Russia are proving they can disagree for independent reasons in any number of theaters.

Well, we ought to make clear to everybody that the next Korean War, if one were ever to happen, is going to be the last Korean War because it's going to end with a unified peninsula, and it's go to be under Seoul, not Pyongyang.

Donald Trump is much more suspicious of international institutions; much more skeptical of the contributions that America's traditional allies have made; more willing, in some cases, to entertain the possibility of getting along with countries who some would call an adversary, such as Mr. Putin's Russia.