With little fanfare, this year marks the 30th anniversary of the Carter Doctrine, when President Jimmy Carter warned against “outside” control of the oil-rich Persian Gulf. The U.S. effectively enforced an implicit corollary to that doctrine—to prevent control by a regional power—in the Iraq wars of 1991 and 2003. But today, the Carter Doctrine must make a powerful and swift return: Iran’s nuclear ambitions threaten the Gulf, posing perhaps the greatest immediate threat to U.S. national security and a great threat to U.S. economic interests by provoking a long-term spike in oil prices.
U.S. President Jimmy Carter came into office declaring the energy challenge the “moral equivalent of war.” He eventually came to designate energy supply as a cause for an actual war. Events in late 1979 conspired to threaten the free flow of oil in the Persian Gulf: Ayatollah Ruhollah Khomeini became supreme leader of the new Islamic Republic of Iran; militants took over the U.S. embassy in Tehran, seizing 53 hostages; armed radicals opposed to the Saudi regime stormed the Great Mosque in Mecca; and the Soviet Union invaded Afghanistan, Iran’s eastern neighbor, bringing Russia closer to its long-held desire to reach the Persian Gulf. The next year, Carter, perceived weak internationally, dramatically expanded the perimeter of the U.S. defensive shield by declaring: “Let our position be absolutely clear: 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.”
The Carter Doctrine is as relevant today as it was thirty years ago. The Persian Gulf’s oil production capacity as a proportion of global demand is roughly the same today—about 28 percent--as it was in 1980. If a hostile power controlled the Gulf, it could unduly influence countries such as China and the U.S., the first and second largest energy consumers, respectively, and play a highly influential role in OPEC, which would effectively hold the global economy hostage to its demands.
Today, the biggest challenge to the Carter Doctrine is Iran’s nuclear ambitions, but not because of the destabilizing fallout of a potential military strike against its nuclear facilities. U.S. or Israeli military action in Iran would trigger a jump in oil prices. However, as long as oil facilities in the Persian Gulf are not dramatically impacted by Iranian reprisals, which is possible, increased Saudi oil production and release of oil stored on tankers and in national reserves could return oil prices to pre-conflict levels within six months. This might derail the fragile global economic recovery, but ultimately the impact could be contained.
A far greater threat to the oil market would be Iran’s attainment of a nuclear weapons capability. The U.S. Fifth Fleet and its other military assets in the region guarantee the free flow of oil through the Persian Gulf. But a nuclear-armed Iran would gain de facto immunity from a conventional attack from another country, significantly limiting the effectiveness of U.S. force projection in the region.
Nevertheless, there is a growing belief in Washington that a nuclear-capable Iran can be contained, just as the Soviet Union was during the Cold War. But while the U.S. could try to impose a nuclear shield around its regional allies and to help contain Iran, it will not be effective. United States’ credibility, so integral to effective deterrence, would be seriously diminished, if after repeatedly issuing warnings to the contrary it permitted Tehran to cross the nuclear threshold. Restoring U.S. credibility would, then, require extraordinary action, while nuclear capability would only embolden the already risk-tolerant Iranian regime. Moreover, the United States lacks politically stable, militarily robust and reliable Arab allies who would permit the permanent stationing of U.S. troops as a tripwire.