There is a fair amount of competition, obviously, with ISIL and the terrorist networks around the world, China also posing a different kind of threat to the rules-based order.

I happen to miss the Constitution; I thought it was a good document.

I think that the only time we will really know what then-President Trump is going to do about the set of challenges that confront him is after he has sat down with his advisers as the commander in chief, when he's looking at the threats and the intelligence from the standpoint of being the number one decider, when he's hearing from his secretary of defense, his chairman, who was the same chairman President Obama had, Chairman Joe Dunford, who is an outstanding public servant, who has led our anti-ISIL effort, on which we're making great progress.

In the 2000 election, George W. Bush, who had shirked military service, succeeded in presenting himself as more reliable on national security than Al Gore.

In the '90s, there was scant presidential leadership and insufficient domestic political mobilization for foreign policy grounded in human rights.

There is a convergence of crises that makes it challenging to keep the world's attention.

As even a democracy like the United States has shown, waging war can benefit a leader in several ways: it can rally citizens around the flag, it can distract them from bleak economic times, and it can enrich a country's elites.