People call me a socialist sometimes. But, no, you gotta meet real socialists. You'll have a sense of what a socialist is.

Our destiny is not written for us, but by us.

If, technologically, it is possible to make an impenetrable device or system where the encryption is so strong that there's no key - there's no door at all - then how do we apprehend the child pornographer? How do we solve or disrupt a terrorist plot?

Some technologies don't pan out; some companies fail. But I will not walk away from the promise of clean energy. ... I will not cede the wind or solar or battery industry to China or Germany because we refuse to make the same commitment here.

Prosperity without freedom is just another form of poverty.

It was not a religion that attacked us that September day. It was al-Qaeda. We will not sacrifice the liberties we cherish or hunker down behind walls of suspicion and mistrust.

As has been well documented, I smoked pot as a kid, and I view it as a bad habit and a vice, not very different from the cigarettes that I smoked as a young person up through a big chunk of my adult life. I don't think it is more dangerous than alcohol.