Lustgarden, writing for the New York Times, has probably the best piece on the national security and geopolitical implications of climate change that I’ve recently come across. The assessment for the USA is not good:
… in the long term, agriculture presents perhaps the most significant illustration of how a warming world might erode America’s position. Right now the U.S. agricultural industry serves as a significant, if low-key, instrument of leverage in America’s own foreign affairs. The U.S. provides roughly a third of soy traded globally, nearly 40 percent of corn and 13 percent of wheat. By recent count, American staple crops are shipped to 174 countries, and democratic influence and power comes with them, all by design. And yet climate data analyzed for this project suggest that the U.S. farming industry is in danger. Crop yields from Texas north to Nebraska could fall by up to 90 percent by as soon as 2040 as the ideal growing region slips toward the Dakotas and the Canadian border. And unlike in Russia or Canada, that border hinders the U.S.’s ability to shift north along with the optimal conditions.
Now, the advantages faced by Canada might be eroded by a militant America, and those of Russia similarly threatened by a belligerent and desperate China (and desperate Southeast Asia more generally). Regardless, food and arable land are generally likely to determine which countries take the longest to most suffer from climate change. Though, in the end, it’s almost a forgone conclusion that we are all ultimately going to suffer horribly for the errors of our ways.