Barack Obama: “It is long past time to end a war that never should have started.”

If I had a blame pie for why politics is so polarised and why we're seeing a rise of populism in many places, it's because of that information that is going into our brains every day.

A drift towards extremism was "not inevitable

I think when we act on that basis, it doesn't always work out, but over time things do get better.

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.