After the discovery of oil in the 1930s, the Gulf monarchies--Saudi Arabia, Kuwait, Qatar, the United Arab Emirates, Oman, and Bahrain--went from being among the world's poorest and most isolated places to some of its most ostentatiously wealthy. To maintain support, the ruling sheikhs provide their subjects with boundless cheap energy, unwittingly leading to some of the highest consumption rates on earth. Today, as summertime temperatures set...