As gas prices climb back toward $4 a gallon, the Obama administration -- facing a tough re-election campaign and rising Middle East tensions -- is once again considering tapping the Strategic Petroleum Reserve. For years, administrations have bought and stored oil for emergencies, in fear of a cutoff of imported oil, as happened during the Arab embargo of 1973-74. But since 2009, the U.S. government has declared most federal lands off-limits to new oil and gas exploration -- despite vast recent finds of energy and radically new means to tap it. President Obama also canceled the most vital sections of...