A lot of politicians, particularly the left-wing set, see Anthropogenic Global Warming (AGW) as an opportunity to increase government control of the world. (Timothy Wirth famously said in 1990 that it didn't matter whether the AGW hypothesis was correct or not, the AGW political agenda was the right thing to do.) There are a few politicians who may actually believe the AGW hypothesis. It is hard to tell about Al Gore. He is not smart enough to have formed his own opinion on the merits of the AGW hypothesis, but he has positioned himself to become the first carbon trading billionaire.