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Has the US lost the Iran war?

On 21 May 2026, the Brookings Institution, a Washington research group, published the transcript of a podcast, Has the US lost the Iran war?. Melanie Sisson hosts. The guests are fellow senior fellows Robert Kagan and Michael O'Hanlon. An American family should care because O'Hanlon estimates what it would take to reopen the Strait of Hormuz, the narrow sea lane for oil leaving the Persian Gulf, by holding the Iranian coast. He says a robust effort means low tens of thousands of U.S. troops in Iran, with a risk of hundreds of casualties and a long stay. That is his planning sketch.

Evidence rating: MODERATE. The rating covers what a named Brookings defense analyst said on the institution's own podcast on 21 May 2026: that holding Iran's coast to reopen the Strait of Hormuz would mean "low tens of thousands of U.S. troops in Iran."

What the article says

The page's own summary says the United States is worse off than before the Iran war. It says Iran now controls the Strait of Hormuz, and that about a fifth of the world's oil must pass through it. The same summary says securing the strait would take thousands of U.S. troops along the Iranian coastline, and that President Donald Trump may walk away without controlling the strait.

Kagan argues that Iran's control of the strait has reversed the balance of power. He says he sees no military way to reopen it without lasting damage to oil facilities. He says that, from Iran's point of view, holding the strait is a question of survival. He also asks what would stop Israel from striking Iran again later. O'Hanlon calls Kagan's case a plausible bad outcome. He is not sure it is the most likely one. He says a deal, or new pipelines years from now, might limit the damage. He says he still sees no real solution, and no net gain for the United States.

Sisson asks how big an operation to reopen the strait would be. O'Hanlon calls his answer a back-of-the-envelope figure. He says the Pentagon's detailed math often lands near that kind of sketch, and that a more precise official number is sometimes proved wrong later. He says holding a coastline of 50 to 100 miles, and protecting the troops rather than only hunting speedboats, means tens of thousands of soldiers. He says a brigade, a unit of several thousand, is typically built to hold about a 25-kilometer front. He says the number changes if the job is heavy combat or only a search for boats.

But I think you're gonna have to have several American brigades plus the support ashore, which means low tens of thousands of U.S. troops in Iran.

Michael O'Hanlon said that on this Brookings podcast, published 21 May 2026. Just before it, he said the operation is doable, but with a risk of hundreds or more American casualties, and a risk that thousands of troops would be bogged down in Iran for a long time. Kagan adds that warships could be lost, and that the real question is whether the United States would pay the cost. His bet is that Trump will declare the war won and leave, and will treat the strait as someone else's problem.

What other reporting and posts add

The same size of force was on the table in March. The Wall Street Journal reported, as Russian state outlet Sputnik relayed it on 27 March, that the Pentagon was considering "up to 10,000 additional ground troops," likely "infantry and armored units," on top of "roughly 5,000 Marines and thousands of paratroopers from the 82nd Airborne Division already ordered to the region." @SputnikInt, 27 March 2026. (capture: twitter/t48__v565.md) Axios reported that the options included to "invade the island of Larak, which helps Iran to control the Strait of Hormuz" and to "seize the island of Abu Musa and two Iranian-controlled smaller islands which are also located near the strait." The Independent, 26 March 2026, citing Axios. (capture: twitter/t56__v668.md) O'Hanlon's "low tens of thousands" to hold a stretch of coast is larger than any of those reported packages.

Kagan's background, as critics raise it. Posts about the war frequently name Robert Kagan as a co-founder, with William Kristol, of the Project for the New American Century (PNAC), the 1990s group that pushed for regime change in Iraq. That is how critics place him; it is background, not a finding about this podcast. (captures: twitter/t05__v059.md, twitter/t30__v351.md)

Who pays if it drags on. Trump himself told Fox & Friends in June he was not sure the country had the appetite for a bigger operation: "I think they'd like to see us come home." See Trump vows to seize Iran's Kharg Island.

What it shows

Even the smallest ground mission on the table, holding a strip of Iran's coast along the Strait of Hormuz, would put "low tens of thousands of U.S. troops in Iran," with a risk of "hundreds or more American casualties" and thousands bogged down for a long time, by the estimate of a mainstream Washington analyst. That coastal mission is the one Axios and the Washington Post reported the Pentagon planning in March, with islands such as Larak and Abu Musa named as targets.

The strait was not reopened from the air. See Kharg Island and the Uranium Raid and Force-Planning Documents.

Check it yourself

The transcript is at https://www.brookings.edu/articles/has-the-us-lost-the-iran-war/

A second essay by O'Hanlon was also opened: How Congress Can Prevent a Quagmire in Iran, Foreign Affairs, 30 March 2026. There he asks Congress to bar a large ground escalation, and he says a coastal presence near Hormuz could still be left open. He does not use the "low tens of thousands" figure in that essay. Kagan's Atlantic article, linked from the podcast, was not opened. A mention of colleague Caitlin Talmadge's writing on mines was not opened either.

Status: Michael O'Hanlon, Robert Kagan, and Melanie Sisson are alive. Donald Trump is alive. This page reports their analysis. It does not accuse them of a crime.

Background for a new reader: the United States and Israel began bombing Iran on 28 February 2026. Iran answered by choking the Strait of Hormuz, and a ceasefire in April did not reopen it fully. The Brookings Institution is a large, long-established Washington think tank generally seen as centrist. Robert Kagan is a well-known foreign-policy writer who has long favored strong American power abroad; Michael O'Hanlon is a defense-budget and force-planning specialist. When two analysts of that kind ask whether the United States has "lost," the question behind it for families is what it would take on the ground to win.

Research captures: twitter/t48__v565.md, twitter/t56__v668.md, twitter/t05__v059.md, twitter/t30__v351.md

Last Updated: 2026-09-26