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.

Our nearly century-long experiment in banning marijuana has failed as abysmally as Prohibition did... In contrast, legalizing and taxing marijuana would bring in substantial sums that could be used to pay for schools, libraries or early childhood education.

Guilt-tripping people does not work; they tend to be turned off.

The greatest threat to extremism isn't drones firing missiles, but girls reading books.

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.

One of the great failings of the American education system (in our view) is that young people can graduate from university without any understanding of poverty at home or abroad.

The tide of history is turning women from beasts of burden and sexual playthings into full-fledged human beings.