I don't know why this ever left the discussion, but Joe Romm points out something rather important at Gristmill: for all the big-big-big numbers thrown around when talking about mitigating climate change, it's worth noting the direct, calculable, brass-tacks benefits. For example, investing in fuel-efficient cars will reduce your gasoline bill.
If we can capture those kinds of efficiencies on a broader level – and there's every reason to think we can – then the costs of mitigating climate change basically pay for themselves. And neither I nor Romm are talking out of our asses here – the International Energy Agency, an OECD body charged with looking ahead on energy issues for the developed world, agrees with us.
Or, to put it the way David Roberts once did (can't find the link right now): if we push for a solution for climate change, we will almost by definition get energy security as a happy side effect. If we push for energy security alone, we are likely to doom the planet with coal-based gasoline. (Please, please, please no Vice-President Schweitzer!)
It's not really that tough a choice, and according to a growing consensus, it will probably save us money in the long run, especially if you think counting pollution as a cost instead of a benefit makes sense.