And so the greatest of American triumphs... became a peculiarly joyless victory. We had won the Cold War, but there would be no parades.

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.

Well, Israel, obviously, thinks of the Iranian nuclear program as an existential threat to Israel.

I've spent my entire adult life with the United States as a superpower and one that had no compunction about spending what it took to sustain that position. And it didn't have to look over its shoulder because our economy was so strong.

I think that Iran with a nuclear weapon is extremely destabilizing. I think it could precipitate a nuclear arms race in the region.

I think that Vladimir Putin is certainly getting a lot of publicity for what the Russians are doing. And I'm not sure that's unwelcome to him. I think this is a guy who saw the U.S. basically come out against him in his reelection campaign in 2012. He saw the U.S. being behind all of the color revolutions in Eastern Europe and in Georgia and Ukraine and so on. So his view is the West has been interfering in his politics for years.

Future U.S. political leaders – those for whom the Cold War was not the formative experience that it was for me – may not consider the return on America’s investment in NATO worth the cost.