We can build a collective civic space large enough for all our separate identities, that we can be E Pluribus Unum - Out of One, Many.

There is no doubt that the issue of race is always present in American politics and in the politics of any multiracial society. There is also no doubt that for some people it is an element in the manifested hostility to Obama. But I don't think it is the major theme at all. Obama is right when he reminds people: By the way, I was black before the election.

I think that asserting that former President Obama wasn't born in the United States was just the height of irresponsibility, of course. And Donald Trump corrected that one. There are others that have yet to be corrected.

The signs that the world is spinning out of kilter are increasingly difficult to misinterpret. The question is how to convince enough people to join a critical mass of urgent opinion, in the U.S. and the rest of the world.

The interior of the earth is extremely hot – several million degrees.

Adopting a central organizing principle means embarking on an all-out effort to use every policy and program, every law and institution, to halt the destruction of the environment.

Mother Nature does not do bailouts.