Thirty-seven years ago, President Jimmy Carter addressed the nation at a joint session of Congress to issue a stern warning to the Soviet Union. The warning established what is known as the Carter Doctrine, which designates the Persian Gulf as a vital national interest of the United States. This doctrine has continued, virtually without change, to dominate U.S. foreign policy—yet the geopolitical conditions and global energy fundamentals have changed dramatically.

On Christmas Day 1979, the Soviet Union invaded Afghanistan. The socialist state eventually deployed more than one hundred thousand troops to the region and placed its armed forces within striking distance of the Strait of Hormuz, through which a great portion of the world’s oil supply transited. President Carter addressed Congress three weeks later and detailed the dangers he believed the USSR posed. The Soviet troops, he said, were seeking to dominate a region that contained two-thirds of the world’s exportable oil and posed “a grave threat” to the free movement of Middle East oil.

“This situation demands careful thought, steady nerves, and resolute action, not only for this year but for many years to come,” he said during the 1980 State of the Union Address. He later added: “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.”

Making the president’s strategic calculus more emphatic was the fact that barely a month before the Soviet invasion, Ayatollah Khomeini sparked a revolution in Iran that had deposed the shah and was still holding Americans hostage, sparking the energy crisis of 1979. By September of 1980, Iran and Iraq were at war, which made the production of crude even more unstable. The threats to Middle Eastern oil were grave.

Nearly forty years later, the Carter Doctrine continues to dominate U.S. foreign policy in the Middle East. The conditions that existed at that time, however, have changed dramatically. Researchers Charles Glaser and Rosemary Kelanic recently published Crude Strategy, a compendium written by scholars and Middle East experts that argues the time is right to revise U.S. policy towards the Middle East. “Since the United States established its commitment, quite dramatic changes have occurred in the regional balance of power, the nature of threats to U.S. security, and global energy trends—all of which bear directly on U.S. interests,” they explained.

In 1980, the United States imported a considerable percentage of its oil from the Middle East. A disruption caused by a Soviet attack back then would have caused significant, and perhaps catastrophic, damage to the U.S. economy. Today, however, the center of gravity for the production of U.S. energy is no longer the Persian Gulf region, but North America.

As of 2015, only 16 percent of all U.S. crude-oil imports came from the Persian Gulf. Saudi Arabia provided 11 percent. North America, however, contributed a whopping 48 percent, with Canada responsible for 40 percent of the total. Meanwhile, beginning in 2008, the United States saw a resurgence in domestic crude-oil production, which has dramatically reduced the amount of oil the country needs to import. However, the idea of “energy independence,” it is important to note, was oft claimed by politicians, but was never based on fact. Even with the dramatic surge of domestic production, the United States still imports 4.7 million barrels of oil per day (mbd), so the security of imported oil will remain of importance to the United States.

In 1980, a hostile superpower was within striking distance of choking off a significant percentage of the oil necessary to power the United States. Not only is that no longer the case, but other nations are now more reliant on Persian Gulf oil than the United States. When the Carter Doctrine was first put into action, the Chinese were an oil exporter. They did not import any oil from the Middle East, but owing to a rapidly growing economy, they became a net oil importer in 1993.

China’s thirst for oil continues to rapidly grow. The country currently imports seven mbd of the twelve mbd it consumes—the vast majority of which comes from the Persian Gulf. Glaser and Kelanic explain that despite slowing economic growth, Beijing’s imports from the Gulf are expected to quintuple by 2030. Should the United States, then, continue to expend a great portion of its national-security budget to keep the Persian Gulf oil flowing for the benefit of China?

Clearly, a reexamination of U.S. strategy vis-à-vis the Middle East is in order. Even with the continued development of domestic oil and gas fields, along with the rise of alternative forms of energy, the United States is going to require some amount of oil from Saudi Arabia. But is that continued interest commensurate with the perpetuation, unaltered, of the Carter Doctrine? The answer is no.

There is presently no major power poised to strike oil facilities in the region. The United States gets no oil from Iran, so even if its exports are blocked in the future (owing to sanctions, for example), that block would have little impact on U.S. imports. The exporting countries themselves have an existential need to export large quantities of oil. For example, regimes in nations such as Saudi Arabia, Kuwait and Qatar are economically dependent on oil revenue to maintain internal stability. It can be argued, therefore, that while Middle Eastern oil remains a U.S. interest, it is no longer a vital national interest. Our security posture and strategy should therefore be updated to reflect current realities and priorities.

Daniel L. Davis is a Senior Fellow for Defense Priorities and a former Lt. Col. in the U.S. Army who retired in 2015 after 21 years, including four combat deployments.

Image: USS John C. Stennis in the Arabian Sea. Flickr/U.S. Navy