I defended this country as a young man, and I will defend it as president.

I know that our country is strongest when we lead the world, when we lead strong alliances. And that's the way Eisenhower and Reagan and Kennedy and others did it.

You cannot bring peace in Syria as long as [Bashar] Assad is, in fact, there.

I get always a little uptight when I hear politicians say how exceptional America is.

When President Bush sees America, he sees only a military superpower. I see a moral and idealistic beacon. Mr. Bush may talk about democracy all he wants, but it is not democracy to wilfully disdain and heap scorn on world opinion. We do not command moral leadership by starting pre-emptive wars.

My definition of patriotism is to defend your country with the truth, no matter the consequences.

I’ve often said that global climate change is an issue where no one has the luxury of being “half-pregnant.” You either are or you aren’t. And so it is with climate change. You either understand and accept the science – or you don’t. Folks this isn’t a cafeteria where you can pick and choose and accept the science that tells us what is happening, but then reject the science that warns us what will happen.