Questions for McCain

You say that even if global warming turns out to be no crisis (the World Meteorological Organization says global temperatures have not risen in a decade), even unnecessary measures taken to combat it will be beneficial because "then all we've done is give our kids a cleaner world." But what of the trillions of dollars those measures will cost in direct expenditures and diminished economic growth—hence diminished medical research, cultural investment, etc.? Given that Earth is always warming or cooling, what is its proper temperature, and how do you know?