Future historians, if there are any, will be dumbfounded. Today, uncountable dollars and unquantifiable hysteria are devoted to the distant threat of climate change milder than some changes Earth has experienced. A recent peer-reviewed study of scientific estimates concludes that the average annual cost of what the excitable U.N. secretary general calls “global boiling” might reach 2 percent of global gross domestic product by 2100. Meanwhile, negligible public anxiety accompanies the intensifying danger of global incineration from nuclear war.