Global warming threatens our health, our economy, our natural resources, and our children's future. It is clear we must act.

I have long said there are three distinct groups under the GOP's tent: theological warriors, who want to impose their social views on the rest of society; Tea Party zealots, who say with a straight face that they want the government to get out of their Medicare; and remnants of the pro-business moderates.

The Republican argument that raising the debt ceiling encourages additional future spending is logically irresponsible. The debt ceiling has to be raised to authorize spending already approved by Congress. Despite that fallacy, the GOP has been able to score political points with its argument.

I don't care about motivation. I care about credibility.

In politics you learn to always smile.

I don't have any particular expertise-I've never been a banker or an investment banker. But I did see an evolution in the system that I thought was problematic.

I don't think Michael Bloomberg would say that his greatest skill is delivering the speech. He would say he's more of a nuts-and-bolts mayor-picking up the trash, dealing with the school system.