The year 2019 may be remembered as an inflection point for the Middle East, when the seemingly intractable violence and instability that have beset the region finally exhausted the United States’ prodigious confidence in its capacity for problem solving. Fifty years ago, the United States began to fill the void left by the British withdrawal from the Persian Gulf and, tentatively at first, take on the role of regional peace broker. For all its flaws—and there were many—U.S. leadership during this period generated some historic dividends, including the 1978 Camp David accords between Israel and Egypt, the 1991 liberation of Kuwait, and the preservation of oil exports in times of intense conflict.
Now, however, the presumption of a vital U.S. interest in promoting peace and security in the Middle East is crumbling under the weight of changing energy markets and the human and financial toll of Washington’s seemingly