Barack Obama: “The American people face no greater or more urgent danger than a terrorist attack with a nuclear weapon.”

I’m going to insist that we can do better than we’re doing right now.

It is a decision about how do we face and embrace this finite amount of time we have on the planet.

When we choose, when we make that decision, I do believe – and there is evidence for this – that the world gets incrementally better, and that is a worthy goal and it’s worth fighting for.

A drift towards extremism was "not inevitable