Mark Ruffalo, aka the Incredible Hulk, is the natural gas industry's worst nightmare: a serious, committed activist who is determined to use his star power as a superhero in the hottest movie of the moment to draw attention the environmental and public health risks of fracking.

Obama wants to be thought of as the president who freed us from foreign oil. But if he doesn't show some political courage, he may well be remembered as the president who cooked the planet.

Americans don't pay much attention to environmental issues, because they aren't sexy. I mean, cleaning up coal plants and reining in outlaw frackers is hugely important work, but it doesn't get anybody's pulse racing.

Have we failed to slow global warming pollution in part because climate and environmental activists have been too polite and well behaved?

Obama wants to be thought of as the president who freed us from foreign oil. But if he doesn't show some political courage, he may well be remembered as the president who cooked the planet.

One of the big questions in the climate change debate: Are humans any smarter than frogs in a pot? If you put a frog in a pot and slowly turn up the heat, it won't jump out. Instead, it will enjoy the nice warm bath until it is cooked to death. We humans seem to be doing pretty much the same thing.