Once you've created a connection of empathy, rational arguments can play a supportive role.

There seems to be this sense among even well-meaning Americans that Africa is this black hole of murder and mutilation that can never be fixed, no matter what aid is brought in.

The intelligence community is so vast that more people have top secret clearance than live in Washington. The U.S. will spend more on the war in Afghanistan this year, adjusting for inflation, than we spent on the Revolutionary War, the War of 1812, the Mexican-American War, the Civil War and the Spanish-American War combined.

Solar power is one of the most hopeful technologies but still produces about 0.01 percent of U.S. electricity. The U.S. allocates just $159 million for solar research per year - about what we spend in Iraq every nine hours.

There is an element of anger among women who've been raped. There's certainly a major element of humiliation. But it really does seem like a medical condition of shock and horror.

Just a little help, a small security force, a bit of food, can save lives

Look, we'll have to confront the pathologies of poverty at some point. We can deal with them cheaply at the front end, in infancy. Or we can wait and jail a troubled adolescent at the tail end. To some extent, we face a choice between investing in preschools or in prisons.