Why Does The US Police The Straits Of Hormuz?

That's the question posed by commenter Cassander:

https://www.bloomberg.com/news/articles/2019-06-26/which-oil-buyers-have-most-at-stake-as-mideast-tensions-rise

Would somebody please explain to me (again) why we are undertaking to police the Straits of Hormuz?

My response was brief:

To insure that India, China, Japan, and S. Korea are supplied with oil.

But there's a longer answer--there has to be, since the topic is such a complicated one. That answer is provided in an article by Anand Toprani--an associate professor of strategy and policy at the U.S. Naval War College, a Term Member of the Council on Foreign Relations, and the author of Oil and the Great Powers: Britain and Germany, 1914-1945 (Oxford: Oxford University Press, 2019).

The article, OIL AND THE FUTURE OF U.S. STRATEGY IN THE PERSIAN GULF, was written in May, 2019, and seems prescient. I remarked earlier today that too much of the commentary on "the current crisis in the Middle East" is simplistic, whereas the situation on the ground--and at sea--is immensely complicated. In saying this I'm not suggesting that Trump's assassination of Soleimani was a mistake--that remains to be seen. What I am suggesting is that US disengagement from the Persian Gulf would not be easy--it would, in fact, have far reaching effects, not all of which would serve US interests. In speaking of disengagement, of course, we need to distinguish between engagement in "policing the Straits of Hormuz," as opposed to policing the whole Middle East. Unfortunately, the Bush and Obama administrations pretty much threw the entire Middle East up for grabs, so Trump's idea of disengagement cannot be easily accomplished.

Toprani provides a pretty comprehensive history of US strategic thinking regarding the Persian Gulf and the oil that flows through it to the world--from 1945 to the present. For our purposes, however, consider the following paragraphs excerpted from the much longer article:

During the Cold War, U.S. officials fretted over the Soviet threat to the Gulf. Recently, scholars have questioned whether the elaborate security infrastructure the United States built in the Gulf during the Cold War was truly necessary. In particular, they have dismissed the economic threat posed by a Soviet occupation of the Gulf. The Soviet Union, as a large oil producer and exporter, had little need for Gulf oil and lacked sufficient foreign exchange to compensate local oil producers for ending exports to the West.

Ironically, the threat today may be greater than during the Cold War. Contemporary China is a far more capable adversary than the Soviet Union. The latter was a pariah within the global economy, whereas the former is one of its manufacturing hubs. In 1946, Soviet per capita income was one-fifth that of the United States. Although the Soviets closed the gap by the 1970s, the collapse in oil prices and stagnation of their economy wiped out any gains. By 1989, the Soviet Union’s GDP (in current dollars) was $506.5 billion, compared to America’s $5.685 trillion. China’s nominal GDP today, by contrast, is more than 60 percent that of the United States, and its foreign exchange reserves total more than $3 trillion.

Combined with its growing demand for oil, China — unlike the Soviet Union — has both the means and the opportunity to incentivize Gulf oil producers to redirect their exports to China and away from other consumers — including U.S. allies in East Asia. A similar scenario occurred in 1915, when Britain bought any cotton the United States was planning to export to Germany and Austria-Hungary after Whitehall added cotton to the list of items covered by its blockade of the Central Powers. This act mollified U.S. cotton exporters (including their congressional patrons), who might have otherwise objected to the loss of their European export markets.

In the past, China was happy to leave the burden of promoting security in the Gulf to the United States. That no longer appears to be the case. Over 80 percent of Chinese oil imports travel through the Indian Ocean and are susceptible to U.S. interdiction. To counter this threat, China is hard at work across the Gulf building partnerships as part of its Belt and Road Initiative. To date, China has secured several long-term supply contracts for oil and liquefied natural gas, measures to facilitate greater Chinese trade and investment, and joint ventures between Chinese firms and local companies in both the Gulf and China. Besides creating new markets for Chinese manufactured goods and supplies of energy less vulnerable to a U.S. blockade, China’s budding economic influence in the Gulf may eventually give Beijing leverage to induce oil producers to adopt policies consistent with Chinese strategic objectives. China analysts warn that Beijing is poised, at least for the time being, to expand its political influence in the Gulf, where its state-directed model of economic development, indifference to human rights concerns, and lack of historical baggage make it an appealing partner.

Would China use this economic leverage in the Gulf to hurt U.S. allies? In the case of U.S. firms with significant business interests in China, Beijing has demonstrated little hesitation in using economic threats — specifically limiting access to China’s domestic market — to extract political concessions. China did the same to a number of South Korean firms in 2017 following Seoul’s deployment of the Terminal High Altitude Area Defense missile system (THAAD). This pressure, and the complaints of South Korean businesses, likely influenced Seoul’s decision to suspend further deployment of THAAD. As the nations of the Gulf become more dependent on their trade with the Far East, so too will their sensitivity to Chinese pressure grow. This is particularly true of Saudi Arabia, which is partnering with Chinese firms to build downstream (oil refining and marketing) and petrochemical assets in China.

The Past and Future of U.S. Strategy in the Gulf

...

How should this history inform future U.S. strategy? Whenever the U.S. military presence in the Gulf becomes politically inconvenient, there arises a chorus that the United States can simply substitute arms sales for “boots on the ground” to guarantee regional peace. Recent arms sales to Saudi Arabia (worth as much as $139 billion since 2009) should dispel such notions once and for all, since they have only fueled Riyadh’s bellicosity toward Iran without increasing its sense of security. None of this should have come as a surprise. There is no evidence that arms sales increase a donor’s leverage over their client — in fact, they often do the opposite. The United States should accordingly limit future arms sales in the region to defensive weaponry.

If the United States cannot outsource regional security to local partners, then the only remaining option is preserving the U.S. military commitment to the region. The current U.S. footprint is relatively small. According to official figures, the total number of active-duty personnel deployed across the Middle East and North Africa (excluding those in Afghanistan, Iraq, Syria, and presumably special forces) is less than 10,000, although the figure including reservists, National Guard units, civilians, and contractors is several times greater. Even then, as a fraction of total U.S. active-duty manpower, the figures are trivial. What is not trivial, however, is the sophisticated logistical infrastructure in the region, particularly Naval Support Activity Bahrain (which hosts U.S. Fifth Fleet), and Al Udeid Air Base (CENTCOM’s forward operating base). Besides supporting partner nations and security cooperation initiatives, these assets are capable of supporting a significant infusion of U.S. troops in the event of a crisis.

...

Conclusion

The fact that the United States is again energy “independent” does not change the underlying rationale for the U.S. presence in the Gulf. The region’s oil remains as vital today as it was after World War II. If we accept the proposition that America’s security is tied to the welfare of its allies and partners, the United States cannot afford to discard the Carter Doctrine, for there is no substitute for the security that U.S. military force provides. If anything, a U.S. withdrawal from the Gulf could encourage China to accelerate the growth of its military capabilities there. U.S. allies such as Japan and South Korea could theoretically redeploy naval assets to the Gulf to protect their oil lifelines, but this would tilt the military balance in the Far East further in China’s favor, thereby undermining the U.S. “rebalance” to Asia.

None of this means the United States cannot learn from its recent mistakes. ...

I hope this essay has demonstrated the continuing significance of Gulf oil to U.S. national security even in an age of U.S. energy self-sufficiency. The question of whether the United States should disengage from the Persian Gulf is intimately bound to the question of whether it still wishes to uphold the international order it painstakingly constructed and maintained after 1945. If it turns out that the American people no longer wish to play that role because they consider the sacrifices incommensurate with the benefits, we can at least begin reassessing U.S. strategy in the Gulf upon a foundation of intellectual honesty.