During the arms race — NATO/WARSAW tension, there was a concept of mutually assured destruction. You may have lots of nuclear warheads, but so do I. So no one can use any of them because we’ll wipe out the entire planet. I’ve been thinking about that in terms of climate change … you chose to do something, you’re going to destroy us all. But … there’s no single collective ‘you’ and no single collective action like, say, the Soviet or American government deciding to launch. And, in the nuclear assured destruction case, the destruction was well understood and immediate. We didn’t deal particularly well with the earlier, easier to comprehend, case of mutually assured destruction. We just kept dumping money into arms and then negotiating to retire out-of-date (and sometimes old-to-the-point-of-getting-dangerous) weapons. How in the world do we hope to force mass short-term changes to ward off hypothetical long-term damages.