If the United States fails to keep Hormuz and the Bab el-Mandeb open, it proves to the world—and its allies in the Middle East—that it cannot be relied upon.

For four decades, American war planners have rehearsed the same nightmare scenario in the Strait of Hormuz: Iranian mines, missiles, and fast-attack boats closing off the strait to commercial traffic, cutting off one-fifth of the world’s oil supply and sending a shock through every economy on Earth.

It is difficult to overstate the impact this scenario has had on American strategic planning. War games have been built around such a crisis, and US aircraft carriers have been repeatedly dispatched to the Middle East to head it off. Preventing an Iranian closure of the strait became the single most important organizing principle of US naval strategy in the Middle East.

That scenario is now in need of an update—not merely because Iran’s ability to close the strait is now clear to all, but because Tehran has developed a strategy that is even more effective. Aided by allied proxy groups elsewhere in the region, Iranian leaders are no longer thinking about Hormuz in isolation. They have concluded that a Hormuz closure could be supercharged by pressure on other notable choke points—most notably the Bab el-Mandeb at the southern terminus of the Red Sea, which can be closed at will by the Iran-allied Houthis in Yemen. Iran is constructing a maritime strategy that binds Hormuz and the Bab el-Mandeb into a single pressure system, in which the disruption of global commerce could become a regular instrument of statecraft rather than a distant doomsday option.

Can Iran Actually Shut Down the Strait of Hormuz? It Doesn’t Matter

The danger was never Iran’s ability to shut down both straits outright. Against the US Navy and its partners, full-on closure for long periods of time is probably not sustainable. The danger, rather, is in Iran’s ability to make passage through those waters persistently and unpredictably unsafe.

In a globalized economy, Iran does not need to close the waterway in order to win; it only needs to prohibitively raise the cost of using it. A naval mine or drone costing tens of thousands of dollars can disable or sink an oil tanker and its cargo, typically costing hundreds of millions. Faced with that risk, ship captains and insurance underwriters will avoid the use of dangerous waterways whenever possible, preferring the steep but predictable cost of a long transit time around the Cape of Good Hope to the small chance of catastrophic loss by sailing through the Bab el-Mandeb. Iran can repeat this scenario over and over again for as long as it wishes.

Tehran has internalized the lesson that it does not need to defeat American naval power in a head-on naval clash. Its objective now is American exhaustion—draining the US Navy’s resources and, more importantly, corroding the credibility on which American power rests. After months of strategically and economically draining low-level warfare, Tehran presumes that American policymakers will be more willing to accept an end to the conflict on the terms it wants—perhaps including US concessions like sanctions relief or asset unfreezing, or even the institution of tolls on ship transit through Hormuz. The more exhausted the United States is, the more appealing these terms will look.

The Persian Gulf and the Red Sea Are One Front, Not Two 

The most consequential analytical error in Washington is the habit of treating the Red Sea and the Persian Gulf as separate battlefields, with separate naval resources allocated to each. From Iran’s vantage point, Hormuz and the Bab el-Mandeb form a single maritime front: Hormuz governs the exit of Gulf hydrocarbons into all world markets, while the Bab el-Mandeb governs their arrival in Europe through the Suez Canal. Taken together, the two waterways account for roughly one-third of all daily oil commerce, and squeezing both at once increases the overall disruption to the global economy and dilutes America’s ability to respond.

This is what the recent belligerency by Iran’s allies against Saudi Arabia—starting last month with the Houthis’ announcement of a blockade on Saudi oil traffic through the Bab el-Mandeb, then Houthi missile strikes on Saudi tankers in the Red Sea and Gulf of Aden, and most recently reports that pro-Iranian militias in Iraq are preparing to strike Saudi ports and airports—has actually delivered for Iran. Some analysts have attributed the Houthis’ actions primarily to disputes with Saudi Arabia and a desire to resume the Yemeni civil war from a position of strength. In truth, however, the escalation has almost nothing to do with events inside Yemen; all signs suggest that the Houthis are acting directly on orders from Tehran. The Houthis have very little to gain from a renewed blockade on its own merits. But Iran gains maritime depth hundreds of miles from its own coastline, compelling Washington to defend multiple corridors at once with finite hulls and finite munitions.

Iran has also learned the need to temper its own escalation in line with political signaling. A genuine attempt to fully close Hormuz, cutting off transit entirely, would create ongoing pressure for a devastating American response. Merely turning Hormuz into a high-risk zone gives Tehran an element of plausible deniability, inviting a far less aggressive response. As long as the strait remains nominally “open” but is littered with naval mines, ship captains will decide on their own not to risk passing through, and the United States cannot reasonably accuse Iran of ongoing obstruction. The strategy is calibrated to stay below the threshold that would justify an escalation in the war that Tehran does not want and would suffer mightily from.

Iran Is Trying to Discredit the “Global Policeman”

The ongoing war is not the first time the United States has become involved in conflict in the Middle East. In the 1970s, President Jimmy Carter promulgated the “Carter Doctrine,” the notion that the United States would use military force to defend its national interests in the Persian Gulf. Carter’s successor in office, Ronald Reagan, launched Operation Earnest Will to protect oil tankers in the Gulf, reflagging Kuwaiti vessels under American colors after the Iran-Iraq War jeopardized freedom of navigation. The administrations of George W. Bush and Barack Obama also responded decisively to the epidemic of Somali piracy near the Horn of Africa in the late 2000s and early 2010s. Although American ships were not the primary victims of that crisis, it imposed billions in additional costs on global commerce, a development that was of direct concern to Washington.

In all of these cases, the United States has been the primary actor responsible for dealing with regional disturbances, and it is expected to remain so in the future. This creates an asymmetric advantage for America’s regional opponents. By creating situations that the US Navy is unable to fully contain, it helps to diminish the US standing in the region and weaken its relationship with local allies.

US policymakers are frustrated about this asymmetry, and rightly so. China, for instance, depends heavily on the Red Sea and Hormuz for its trade and energy imports. It operates a military base in Djibouti, within reach of the Bab el-Mandeb, and it could contribute to regional security if it wished. Yet Beijing contributes almost nothing to securing the system it relies on; since 2023, it has repeatedly cut deals with the Houthis to allow its own ships to pass, leaving the United States to sort out the problem for everyone else.

That arrangement was perhaps tolerable when American primacy was uncontested and the burden of global leadership was relatively cheap. It is becoming untenable as asymmetric threats proliferate, as interceptor inventories grow thinner, as the Indo-Pacific consumes more attention, and as the gap between what Washington guarantees and what it can sustainably underwrite widens.

America Must Stay Strong—and Its Allies Must Support It

To meet this new reality, the United States needs to redefine maritime security in the region. Its reactive episodic strikes after each attack have demonstrably failed to restore deterrence. What is required now is an integrated approach that treats the sea lanes from the Gulf to Suez as one strategic theater: unified command attention, greater burden-sharing with European and regional partners and other global powers, intelligence focused on interdicting the supply chains that arm the proxies, cyber capabilities directed at targeting networks, and protection extended to the submarine cables and energy infrastructure that are the next obvious targets.

The United States must also reliably impose costs on the states that enable proxy attacks, not merely on the proxies themselves. If the Houthis close off the Bab el-Mandeb, the United States has limited options for retaliating directly against Houthi targets. A more effective strategy would be to directly impose greater consequences on Iran, ignoring Tehran’s veneer of plausible deniability. Above all, it must demonstrate that it can and will reliably inflict pain on rogue regional actors intent on diminishing its credibility before its allies.

The implications extend far beyond the Middle East. If Iran succeeds in establishing a model in which inexpensive drones, missiles, naval mines, and proxy forces can impose disproportionate costs on the world’s most powerful military and threaten the arteries of global trade, others will take notice. Any nation or non-state actor overlooking a critical waterway can hold that waterway to ransom, with catastrophic consequences for the global economy. Conversely, if Washington restores credible deterrence before this model becomes the new normal, it will have protected far more than the Strait of Hormuz or Bab el-Mandeb: it will have defended one of the defining principles of the post-1945 international order, and illustrated that the United States can keep the global commons open and secure—if no longer alone, then at least with the assistance of its global network of allies and partners. That principle, not the security of any single waterway, is the true foundation of American leadership.

About the Author: Khalid Al-Jaber

Dr. Khalid Al-Jaber serves as the executive director of the Middle East Council on Global Affairs in Doha. A leading researcher and academic, he is widely recognized for his expertise in international relations, political communication, and the dynamics of the Middle East and North Africa (MENA) region.

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