We've said to the Iranians all along . . . we still remain open to diplomacy. But it's been very clear that the Iranians don't want to engage with us.

If we're going to prevent large parts of this Earth from becoming not only inhospitable but uninhabitable in our lifetimes, we're going to have to keep some fossil fuels in the ground rather than burn them and release more dangerous pollution into the sky.

A little reminder to those who don't back Obama and gay marriage. It's probably cause you're gay.

One thing you learn in this job [being US President] is that even if something's not your fault, you're still responsible. And that's how it should be.

I accept that people are going to call me awful things every day, and I will always defend their right to do so.

The arc of the moral universe may bend towards justice, but it doesn't bend on its own.

My particular passion for Lincoln dates back from my earliest memories of politics.