Waxman markey and GDP

Conor Clarke counters Manzi:

I think there's a fair amount of scaremongering going about the costs of cap and trade. I get off the Jim Manzi train when he says that Waxman-Markey will be "a terrible deal for American taxpayers" because "it is projected to impose annual costs of about $1,100 per household (a little less than 1% of total consumption) by 2050." (That's from the EPA estimate.) That $1,100 looks like a lot, but of course the country is projected be almost three times richer in 2050 than it is now. Average household consumption in 2050 will be $164,348.

This does put things in perspective, but what are we getting for that 1% decrease? By Manzi's estimate: "If the law works precisely as intended, in about one hundred years we should expect surface temperatures to be a about one-tenth of one degree Celsius lower than they otherwise would be." Small benefit; trivial cost. And that's the problem.