The most striking thing is that even before Osama bin Laden was killed, he seemed largely irrelevant to the Arab Spring.

If the Arab world today looked like Tunisia, it would be a huge blow for the extreme ideologies. But Tunisia needs more support than it is getting, particularly from their close neighbors in Europe who have a great stake in North Africa.

We are already seeing a degree of instability in the world because Obama seems to have consciously wanted to step back. Donald Trump is going to be "Obama squared," a more extreme version of the same thing.

NATO is still the most remarkable alliance in history. It stuck together through 40 years of Cold War, and it then joined together to fight in Afghanistan. In the 1980s, I would not have thought this was going to be possible.

The Bernie Sanders phenomenon shows that it's not confined to Republicans. There is a general sentiment that America is on the wrong track.

Our security depends on having good relationships with our allies. Donald Trump mainly shows contempt for them.

I'm constantly asking for alternative views on most things that come to me.