On domestic policy, one of the major stories in American politics has been the growing ideological and political self-confidence of the Democratic Party, and the growing ideological and political pessimism of the Republican Party.

The top line is that hubris is a disease that comes from success.

Our sense of optimism, our can-do spirit, that's a source of great strength in America. But when there are no limits at all and we've gone through whole periods where we think everything has gone right, that's when disaster tends to strike.

It's easy to see why conservatives would be salivating at the thought of a Hillary primary challenge. Presidents who face serious primary challenges—Ford, Carter, Bush I—almost always lose. The last president who lost reelection without a serious primary challenge, by contrast, was Herbert Hoover. But in truth, the chances that Obama will face a primary challenge are vanishingly slim, and the chances that he will lose reelection only slightly higher. No wonder conservatives are fantasizing about Hillary Clinton taking down Barack Obama. If she doesn't, it's unlikely they will.

I think the tragedy of Barack Obama's presidency is that although a lot of people around the world really admire Barack Obama a lot, they don't admire the American political and economic model as much as they used to.

I think the most inspiring thing that Americans can do for the rest of the world is struggle against the evils in our own society.

Fears don't exist in isolation. They tend to rise and fall depending on what people think they can do about them.