Hmm, not simple at all. Seems a bit of a straw man argument to me.
How do we know that the costs incurred in column 1 will *actually* fix global warming? We might get the whole "end of the world" stuff with added cost, which would be better spent saving ourselves from the tsunamis, hurricanes and other doomsday scenarios rather than mucking around with expensive carbon emission controls and regulations.
For a counterargument, this documentary was shown on UK TV a while ago and is available in 8 parts.
www.youtube.com/watch?v=8f8v5du5_ag
It is also quite biased, but it's good to open your mind about the issues. The science isn't clear that we're causing global warming, and it isn't clear that even if we are there's anything reasonable we can do about it.