“To what do you attribute the greatest cause of global warming?”

At 1:20 in the morning, I am “somewhat informed about global warming”, “hell yes concerned about it [...] but the Kyoto protocol won't do a damn thing”, feel that US efforts rate a 3 “compared to other nations' efforts at combating global warming” where “US” is not well-defined, and “don’t really give a fuck about current data that supports the argument that excessive fuel use is contributing to climate change”. [Sorry, but I am being given a survey at 1:20AM.]