If any individual who objects to government policy can take it in their own hands to publicly disclose classified information, then we will never be able to keep our people safe or conduct foreign policy.

If there is anyone out there who still doubts that America is a place where all things are possible; who still wonders if the dream of our founders is alive in our time; who still questions the power of our Democracy; Tonight is your answer.

America and Islam are not exclusive and need not be in competition. Instead, they overlap, and share common principles of justice and progress, tolerance and the dignity of all human beings.

No one nation can or should try to dominate another nation.

Hope is not blind optimism. It's not ignoring the enormity of the task ahead or the roadblocks that stand in our path. It's not sitting on the sidelines or shirking from a fight. Hope is that thing inside us that insists, despite all evidence to the contrary, that something better awaits us if we have the courage to reach for it, and to work for it, and to fight for it. Hope is the belief that destiny will not be written for us, but by us, by the men and women who are not content to settle for the world as it is, who have the courage to remake the world as it should be.

I'm a big believer in tolerance. I think that religion at it's best comes with a big dose of doubt.

Scientists and engineers ought to stand side by side with athletes and entertainers as role models.