For Iran, Flexing Control Over Waterway Is New Deterrent

For Iran, Flexing Control Over Waterway Is New Deterrent

Iran’s government could emerge from the conflict with a blueprint to keep adversaries at bay, regardless of any restrictions on its nuclear program.

 

Mark Mazzetti Adam Entous Julian E. Barnes

By Mark MazzettiAdam Entous and Julian E. Barnes

Reporting from Washington

https://www.nytimes.com/2026/04/18/us/politics/iran-hormuz-strait-trump.html

April 18, 2026

 

The United States and Israel launched their war against Iran on the argument that if Iran one day got a nuclear weapon, it would have the ultimate deterrent against future attacks.

 

It turns out that Iran already has a deterrent: its own geography.

 

Iran’s decision to flex its control over shipping through the Strait of Hormuz, the strategic choke point through which 20 percent of the world’s oil supply flows, has brought global economic pain in the form of higher prices for gasoline, fertilizer and other staples. It has upended war planning in the United States and Israel, where officials have had to devise military options to wrest the strait from Iranian control.

 

The U.S.-Israeli war has significantly damaged Iran’s leadership structure, larger naval vessels and missile production facilities, but it has done little to restrict Iran’s ability to control the strait.

 

Iran could thus emerge from the conflict with a blueprint for its hard-line theocratic government to keep its adversaries at bay, regardless of any restrictions on its nuclear program.

 

 

“Everyone now knows that if there is a conflict in the future, closing the strait will be the first thing in the Iranian textbook,” said Danny Citrinowicz, a former head of the Iran branch of Israel’s military intelligence agency and now a fellow at the Atlantic Council. “You cannot beat geography.”

 

In several social media posts on Friday, President Trump said that the strait, which in one post he called the “Strait of Iran,” was “completely open” to shipping. Iran’s foreign minister made a similar declaration. On Saturday, however, Iran’s Islamic Revolutionary Guard Corps said that the waterway remained closed, suggesting a divide among Iranian military and civilians on the issue  during negotiations to end the war.

 

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Whereas just the prospect of sea mines is enough to scare off commercial shipping, Iran retains far more precise means of control: attack drones and short-range missiles. American military and intelligence officials estimate that, after weeks of war, Iran still has about 40 percent of its arsenal of attack drones and upward of 60 percent of its missile launchers — more than enough to hold shipping in the Strait of Hormuz hostage in the future.

 

A central goal of the U.S.-led military campaign in Iran is now reopening the strait, which was open when the war began. It is a precarious position for the United States, and its adversaries have taken notice.

 

“It’s not clear how the truce between Washington and Tehran will play out. But one thing is certain — Iran has tested its nuclear weapons. It’s called the Strait of Hormuz. Its potential is inexhaustible,” Dmitri Medvedev, a former president of Russia and deputy chairman of the country’s security council, wrote on social media last week.

 

Iran’s control over the strait forced President Trump to announce a naval blockade of his own, and this week the U.S. Navy began forcing cargo ships into Iranian ports after they transited the waterway.

 

Iran responded with anger, but also taunting. “The Strait of Hormuz isn’t social media. If someone blocks you, you can’t just block them back,” one Iranian diplomatic outpost, which has posted snarky messages throughout the war, wrote on X in response to Mr. Trump’s move. The dispute over the strait has been the focus of numerous A.I.-generated videos depicting American and Israeli officials as Lego characters.

 

Still, the impact of the American blockade has been real. Seaborne trade accounts for roughly 90 percent of Iran’s economic output — approximately $340 million per day — and that flow in recent days has largely ground to a halt.

 

Iran considers the blockade an act of war and has threatened to attack it. But so far it has not, nor has the United States tried during the current cease-fire to reduce Iran’s grip over the strait when the conflict finally ends.

 

“It may be that both countries see there is a real window to have negotiations” and don’t want to escalate the conflict right now, Adm. Kevin Donegan, who once commanded the U.S. Navy’s fleet with responsibility for the Middle East and is now retired, said during a seminar hosted by the Middle East Institute this week.

 

Iran tried to block the Strait of Hormuz once before, mining it and the Persian Gulf during the conflict with Iraq during the 1980s. But mine warfare is dangerous, and decades later Iran has effectively harnessed missile and drone technology to threaten both commercial and military maritime traffic.

 

While the U.S. and Israeli war significantly damaged Iran’s weapons manufacturing capability, Iran has preserved enough of its missiles, launchers and one-way attack drones to put shipping in the strait at risk.

 

U.S. intelligence and military estimates vary, but multiple officials said that Iran has about 40 percent of its prewar arsenal of drones. Those drones have proved to be a powerful deterrent. While they are easily shot down by American warships, commercial tankers have few defenses.

 

Iran also has ample supplies of missiles and missile launchers. At the time of the cease-fire, Iran had access to about half its missile launchers. In the days that immediately followed, it dug out about 100 systems that had been buried inside caves and bunkers, bringing its stockpile of launchers back up to about 60 percent of its prewar level.

 

Iran is also digging out its supply of missiles, similarly buried in rubble from American attacks on its bunkers and depots. When that work is done, Iran could reclaim as much as 70 percent of its prewar arsenal, according to some American estimates.

 

Officials note that the counts of Iran’s weapon stocks are not precise. Intelligence assessments offer a broad look at how much power Iran retains.

 

But while estimates of Iran’s missile stockpiles differ, there is agreement among officials that Iran has enough weaponry to halt shipping in the future.

 

Iran’s government chose not to block the Strait of Hormuz last June, when Israel launched a military campaign that United States eventually joined to hit deeply buried nuclear sites.

 

Mr. Citrinowicz, the former Israeli official, said that decision probably reflected the cautious approach of Iran’s supreme leader, Ayatollah Ali Khamenei, who may have been concerned that blocking the strait could have led other countries to join the military campaign against Iran.

 

Ayatollah Khamenei was killed during the first day of the current war, a move that signaled to Iranian officials that American and Israeli goals for this conflict were far more expansive.

 

Iran “saw the June war as an Israeli war for their own strategic objectives,” Mr. Citrinowicz said. “This is a regime change war.”

 

Eric Schmitt contributed reporting.

 

Mark Mazzetti is an investigative reporter based in Washington, D.C., focusing on national security, intelligence, and foreign affairs. He has written a book about the C.I.A.

 

Adam Entous is a Washington-based investigative reporter focused on national security and intelligence matters.

 

Julian E. Barnes covers the U.S. intelligence agencies and international security matters for The Times. He has written about security issues for more than two decades.