Barack Obama: “We can't afford four more years of George Bush foreign policy. That's why we can't afford John McCain.”

The fact that any president, or any administration, is willing to engage in such transparent efforts to intimidate someone should outrage all Americans, regardless of how they feel about Congresswoman Omar’s political views.

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.

And I will fight for that, even if I don’t always think it’s going to win.