In a world of complex threats, our security and leadership depends on all elements of our power - including strong and principled diplomacy.

By 2016, the people who had looked to [Barack] Obama for change were looking somewhere else.

Honestly this is not going to change unless the people who want to prevent these kinds of mass shootings from taking place feel at least as passionate, at least as mobilized and well-funded as the NRA and the gun manufacturers are because the politics in Congress are such where even members of Congress who know better are fearful if they vote their conscience and support common sense measures like background checks, they're worried they're going to lose.

There are problems that just end up being really hard and by definition the only problems that come to my desk are the ones that nobody else can solve.

Alongside my own deep personal faith, I am a follower, as well, of our civic religion. I am a big believer in the separation of church and state.

True leadership will not be measured by the ability to muzzle dissent, or to intimidate and harass political opponents at home. The people of the world want change. They will not long tolerate those who are on the wrong side of history.

I think the Turks' willingness to take seriously action on the borders to stop the flow of foreign fighters joining ISIL is significant.