The Middle East first came to dominate U.S. defense policy in the 1970s — the decade of the Arab oil embargo, the Iran hostage crisis and the Soviet invasion of Afghanistan. Back then, the United States was dependent on Middle Eastern oil, leading President Jimmy Carter to announce a new doctrine in 1980: “An attempt by any outside force to gain control of the Persian Gulf region will be regarded as an assault on the vital interests of the United States of America, and such an assault will be repelled by any means necessary, including military force.”

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