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.

We all might ask ourselves why we tune in to these more trivial matters and tune out when it comes to Darfur

Sandy was particularly destructive because it was prevented from moving back out to sea by a "blocking pattern" associated with the jet stream. There's debate about this, but one recent study suggested that melting sea ice in the Arctic may lead to such blocking.

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.

You could perhaps better tell the story of a place by writing of a tiny village as a sort of prism into the bigger issues the culture was facing. It struck me as a better way to learn about a place, or at least a different way, than just going to interview the president. So I have often tried to tell the story of a place through people there. But I'm just amazed.

Half a million women die each year around the world in pregnancy. It's not biology that kills them so much as neglect.

I think that [Donald] Trump is frankly a bigot. He has a racist history.