We should be more modest in our belief that we can impose democracy on a country through military force.

The science [of global warming] is beyond dispute... Delay is no longer an option. Denial is no longer an acceptable response

After a decade of profligacy, the American people are tired of politicians who talk the talk but don't walk the walk when it comes to fiscal responsibility. It's easy to get up in front of the cameras and rant against exploding deficits. What's hard is actually getting deficits under control. But that's what we must do. Like families across the country, we have to take responsibility for every dollar we spend.

There is no excuse for not trying.

The bottom line is this - whereas Iran was steadily expanding its nuclear program, we have now cut off every single path that Iran could have used to build a bomb.

Around the world, Gandhi, Nelson Mandela -- what they did was hard. It takes time. It takes more than a single term. It takes more than a single president. It takes more than a single individual.

I don't want ever to be a president who is comfortable and at ease with killing people.