How to Isolate Tehran

U.S. President Donald Trump is never at a loss for words when it comes to the war with Iran. He is having a harder time conveying clear objectives in his war of choice. As U.S. officials weigh their unappealing options for getting to an acceptable endgame, the Trump administration’s war aims remain as confused today as they were when the U.S.-Israeli military campaign began on Feb. 28.

In February, the Trump administration could not decide if its aim was toppling the regime or degrading Iran’s military means to threaten its neighbors. The irony is that if Trump had only attacked Tehran’s military might and not its leadership, the Iranians would almost certainly not have shut down the Strait of Hormuz. Ayatollah Ali Khamenei, the late Iranian supreme leader, had avoided doing so since 1988, believing that closing the strait would provoke a war with the United States that could threaten the survival of the Islamic Republic. But once Trump and the Israelis sought to decapitate the regime by killing Khamenei, Iran’s leaders concluded that they had nothing to lose. Now, however much the Trump administration may talk about ensuring that Iran never acquires nuclear weapons, the U.S. preoccupation is getting the Strait of Hormuz reopened and operating as it was prior to the war.

The problem is that the Iranians seem determined to remain in control of the strait. They see it as a “trump card,” giving them leverage over the global economy, inflicting domestic political pain on the hated Trump, and forcing their Gulf neighbors and others to pay them off both economically and politically. Mohsen Rezaei, a member of the old guard of the Islamic Revolutionary Guard Corps (IRGC) and an advisor to the new supreme leader, declared recently that the strait is “more important than dozens of atomic bombs.”

As a result, Trump is left with three basic options to end the war. First, he can stay on his present course, using military strikes to weaken the Iranians. Having renewed the U.S. blockade on Iran, Trump will be raising the costs to the Iranians at a time when their economy is in desperate shape. The president’s claims to have reopened the strait are hollow, and the Iranians will have a strong incentive to prevent others from transiting if they can’t.

That is likely to lead to more of the kind of relatively limited military exchanges we are seeing now but with each side keeping its military strikes within bounds. Trump will do so because he does not want oil facilities to become targets lest the price of oil goes up dramatically; the Iranians will do so because they think they can outlast the president. The upside of this option is that the costs will grow for Iran, and even an IRGC-dominated leadership in Tehran won’t be able to indefinitely ignore the domestic strain. The downside, from Trump’s perspective, is that oil prices and inflation will rise. Still, the increasing pressure on Iran’s economy (and the ongoing weakening of its forces) could bring Tehran back to negotiations in a way that could make a real deal possible.

Second, the United States could restore Project Freedom, its operation to help escort commercial vessels through the Strait of Hormuz. This would entail degrading Iranian military capabilities so that the IRGC leadership begins to lose its ability to threaten Iran’s neighbors and international shipping. Taking away Hormuz as a trump card would leave the Iranians vulnerable and deprive them of their key leverage. But doing so would likely require taking some of the Iranian islands in the strait and destroying a high percentage of Iran’s missiles, launchers, and drones.

This all sounds highly desirable, but would it be achievable at an acceptable price? The United States would definitely suffer casualties if Central Command seized any of the Hormuz islands or Iranian coastal areas. Moreover, it would have to take out Iran’s deep underground tunnels—where Tehran’s missiles and launchers escaped destruction during the joint U.S.-Israeli bombardment. Perhaps focusing not on Iran’s leadership and the Basij and IRGC headquarters but on the tunnels could produce far better results. If so, Iran might become far more amenable to the Trump administration’s demands about its nuclear program and Hormuz. But this mission could be costly or unachievable anytime soon, or it is almost certain to lead the Iranians to attack other Gulf states’ energy targets.

The president’s third option is to double down on his war. This might be the most Trumpian. He could conduct massive strikes against the Iranian military and, at the end of seven to 10 days of bombing, declare it a great success. As Trump crows of having weakened Tehran, he could also say he is ready to end the war and lift the U.S. blockade if Iran allows transit through the strait. He might also declare that any effort by Iran to extract its highly enriched uranium from beneath the rubble at Fordow or Isfahan will produce more U.S. bombing. Trump has already indicated that he might bomb Pickaxe Mountain, a site near Natanz where the Iranians appear to be trying to build an underground nuclear enrichment facility.

U.S. officials said on Wednesday that Trump is leaning toward wider military operations, perhaps including ground operations against Iranian islands. This would be risky. While lifting the blockade in return for Iran reopening Hormuz might seem the logical trade-off, the Iranians are unlikely to accept it unless they have been hurt enough to want or need a way out of the war. For Iran’s new, IRGC-dominated leadership, there is little prospect of that, for two key reasons: They will not want to look as if they are giving in to Trump after another week of intensive bombing, and his desire to end the war will be palpable to them. Since he wants the war over with, the IRGC will seek something for it.

So, what should Trump do instead? The best—or least bad—option would be to combine the U.S. blockade with forceful and sophisticated diplomacy. As noted above, the blockade is slowly raising the war’s costs to the Iranians and weakening their leverage. But on its own, it is not enough. A winning strategy requires doing something the Trump administration has long avoided: using diplomacy not just for talks but to mobilize others, reinforce U.S. actions, and apply collective (and not unilateral) pressure.

For this approach to work, Iran needs to see and feel isolated and discredited on Hormuz. It needs to see the Europeans and the Arabs offer a U.N. Security Council resolution that insists that the strait remain an international waterway, not controlled, monetized, or managed by any member state. Trump needs to work with the Saudis and the Emiratis to tell China that they expect Beijing to support such a resolution—and to warn that failing to do so will carry consequences for their relationships. A Chinese decision not to block such a resolution would be a shock to Tehran. Iran is not North Korea: The Islamic Republic’s leaders see themselves as the heirs to a rich historical, national, and cultural legacy, and preventing isolation matters to them.

None of this will be easy. The essence of good statecraft is marrying objectives and means, and doing so is impossible when the objectives are muddled. Smart statecraft would involve using all tools—political, economic, diplomatic, military, intelligence—to isolate Iran and raise the costs of running the strait. Trump wants to end this war with Iran weaker and not in control of Hormuz. Force alone will not produce that endgame—but diplomacy that is integrated with the use of force and tied to increasing economic pressure just might allow him to shape a deal to end his war.

Dennis Ross is the Davidson Distinguished Fellow at The Washington Institute, author of Statecraft 2.0: What America Needs to Lead in a Multipolar World, and a former senior U.S. official in the Reagan, Bush, Clinton, and Obama administrations. This article was originally published on the Foreign Policy website.