The United States is the world's largest oil producer, pumping some 13 million barrels every day. Yet the U.S. is also the biggest consumer of crude, a major exporter, and a country with an empty strategic petroleum reserve. Continental Resources founder Harold Hamm called the U.S. "unusually vulnerable" to an oil shock. Just a month ago, such a shock looked rather unlikely. The war in the Middle East had been going on for a year now, and oil supply had not been disturbed. It all changed this week after Iran carried out a barrage of precision missile…
