I don't know why you should be proud of something. It doesn't make you any better or worse. You are what you are.

Fifty percent of the world's population lives in cities. In a couple of decades, 70 percent of the world's population will be living in cities. Cities are where the problem is. Cities are where the solution is, where creativity exists to address the challenges and where they have most impact. This is why, in 2005, the C40 was founded, an organization of cities that address climate change. It started with 18 cities; now it's 91. Cities simply are the key to saving the planet.

If you want to do something for your children and show how much you love them, the single best thing-by far-is to support organizations that will create a better world for them and their children.

If you really believe that you're making a difference and that you can leave a legacy of better schools and jobs and safer streets, why would you not spend the money? The objective is to improve the schools, bring down crime, build affordable housing, clean the streets - not to have a fair fight.

I have my own army in the NYPD, which is the seventh biggest army in the world. I have my own State Department, much to Foggy Bottom's annoyance. We have the United Nations in New York, and so we have an entree into the diplomatic world that Washington does not have.

Most gun dealers follow the law and run honest businesses. But the statistics show that 1 percent of dealers sell more than half of all illegal guns. Why isn't the federal government going after them? Here's one reason: unlike mayors, members of Congress don't get a phone call in the middle of the night when a cop is shot and killed. They don't deliver the eulogies.

We're America, and we have to stop worrying about what happens overseas, and to be optimistic, even though nobody should think we're not going to have some difficult times.