By Michael R. Gordon and Jared Malsin

When President Trump voiced hope last weekend that the air war he was unleashing against Iran would topple the country's regime, he was making a bet against history.

Never before have warplanes, missiles and bombs been enough on their own to remove one government and replace it with another. The U.S. military has upended governments in the past, but all of those operations have required troops or at least an indigenous force.

Trump has made no secret of his desire for regime change. Hours after launching the first airstrikes, he called on Iranians to rise up against their government, saying it "will probably be your only chance for generations." On Thursday, he said he must be involved in picking Iran's next leader, and followed that up on Friday, writing on Truth Social that the U.S. will insist on an "UNCONDITIONAL SURRENDER" and "the selection of a GREAT & ACCEPTABLE Leader(s)" before making a deal to "bring Iran back from the brink of destruction."

But U.S. military leaders have sought to temper expectations in public briefings of what the war might accomplish. The objective, they say, is to strip Iran of ballistic missiles, one-way attack drones and ships that threaten U.S. forces and allies, while also finishing off the remnants of the country's nuclear program.

Adm. Brad Cooper, the head of the U.S. Central Command -- which is overseeing the war, told reporters Thursday that U.S. strikes could benefit Iran's opposition by "targeting the headquarters and the people who are targeting the protesters" and urged the Iranian people to stay in their homes and "lay low."

But the U.S. military hasn't promised to oust Iran's regime or take steps to bring a new set of leaders to power in Tehran, such as arming the opposition or providing air cover for a potential rebellion.

Differences also have emerged between the U.S. and Israeli war aims. Elbridge Colby, the Defense Department's top policy official, told Congress on Tuesday that the Pentagon was pursuing "scoped and reasonable objectives" by focusing on Iran's offensive military capabilities. When asked by lawmakers why the war had begun with an airstrike that killed Iranian Supreme Leader Ayatollah Ali Khamenei, he gave a blunt response: "Those are Israeli operations."

Airstrikes have long been a go-to way to project military power for U.S. administrations that want to minimize the risk of American casualties and avoid entangling ground wars. U.S. military officials say they have greatly reduced Iran's ability to launch ballistic missiles and have sunk much of the country's navy. But without U.S. or local ground forces, they have never toppled and replaced a foreign government.

"Air power alone can do a lot of things well, but regime change is not one of them," said Frank Kendall, who was Air Force secretary under President Joe Biden.

Digging in

For all of the Israeli and American firepower raining down on Iran, the attacks have yet to remove the core structures of the regime, all designed to quash dissent at home and endure external shocks.

The Islamic Revolutionary Guard Corps, established in 1979 to ensure the survival of the revolutionary regime, includes 190,000 active-duty soldiers. Those are separate from the more than 300,000 soldiers in Iran's conventional army and about 600,000 irregular basij militia that the regime can mobilize, according to estimates from the International Institute for Strategic Studies think tank.

After Khamenei was killed, the regime convened an 88-member assembly, which named his son Mojtaba as the new leader.

If the regime were to buckle or fall, one early sign would be defections from those forces or simple acts of refusal to follow orders among the ranks, as happened during Iran's 1979 revolution that brought the current regime into being. Other indications that the regime's grip was weakening could include major industrial action, such as a strike among oil workers.

The fog of war during the conflict's early days makes it difficult for U.S. experts to identify those indicators, and some experts are skeptical they will emerge.

"We're not seeing it, and we're unlikely to see it," said Alan Eyre, a Farsi-speaking former diplomat who served on the U.S. nuclear negotiating team with Iran. "The IRGC and other elites benefit the most from the status quo and would rather fight than switch."

If the regime does fall, the establishment of a new government in Iran could provide Washington with a partner the U.S. and Israel might work with to stabilize the country, secure Iran's supplies of enriched uranium and rule out the possibility that stocks of hidden missiles, drones and sea mines might remain.

But another scenario is that the Iranian regime survives while the administration around it largely collapses -- an outcome that might foment chaos in a country of more than 90 million people that sits astride the world's most important energy shipping lane in the Persian Gulf.

The survival of the regime also would present Trump with a difficult dilemma: stick with an air and naval campaign that can keep reducing Iran's offensive capabilities, or expand the operation's scope by taking additional steps to back political factions or separatist groups inside the country.

On Wednesday, White House press secretary Karoline Leavitt said that sending U.S. ground troops to Iraq wasn't part of the current plan, but late Saturday Trump said they could be used if there was "a very good reason."

Trump's recent calls to Kurdish officials in Iraq spurred speculation that he was hoping to encourage attacks against the regime by Kurdish fighters in neighboring Iran. But Trump also said Saturday that he had ruled out the idea because the "the war is complicated enough without having, getting the Kurds involved." Even if the White House took such steps, the Kurdish minority would represent at best another point of pressure on Tehran but wouldn't be seen as a viable force to govern the country.

"Ultimately, there has to be a political process. There has to be somebody who can step into the void and begin the hard work of government," said Joseph Votel, a retired four-star Army general and former head of Central Command.

History's lessons

The theory that air power can deliver a decisive victory was outlined by Italian Gen. Giulio Douhet, who argued in a 1921 treatise, "The Command of the Air," that strategic bombing could win a war by destroying a nation's "vital centers," which he defined as industry, transportation, communications, government and "the will of the people."

His contention that bombing industrial centers would lead to a speedy victory was seen by many as a response to World War I, and the long slog of trench warfare. But it was controversial at the time and didn't pan out in practice.

Although bombing contributed to Germany's defeat in World War II, it took ground offensives by the Allied powers to win that war. U.S. incendiary attacks on Tokyo didn't force Japan's surrender, which only occurred after the U.S. went beyond conventional airstrikes and dropped two nuclear bombs on Japan five months later.

Decades later, the emergence of stealth technology and precision guided weapons revived the idea that airstrikes could be decisive. Col. John Warden, who led an Air Force directorate in the 1980s that was tasked with developing new ideas to apply air power in a conventional war, argued that the U.S. had the means to induce "strategic paralysis" that would eliminate the adversary's ability to effectively marshal its military forces.

That approach was incorporated in the 1991 "Desert Storm" campaign, in which a U.S.-led coalition evicted Iraqi troops from Kuwait. The 38 days of airstrikes proved highly effective. Even so, the campaign didn't end until after a four-day ground war. Some senior George H.W. Bush administration officials, backed by the Saudis, weren't supportive of wholesale regime change, though the military sought to bomb Saddam Hussein, who was also commander in chief of Iraq's armed forces.

Since then, American air power has played an essential role in defeating adversaries, though successful operations to oust regimes have drawn on U.S. or local ground forces. The 78-day air campaign in 1999 by the U.S. and its North Atlantic Treaty Organization allies that reversed the Yugoslav army's attacks on Kosovo benefited from resistance on the ground by a separatist Kosovo militia, the Kosovo Liberation Army, and warnings by the British military that it might go in on the ground.

In 2011, U.S. and allied air power led to the end of the regime of Libyan strongman Moammar Gadhafi, though it required the help of opposition forces on the ground. After a brief period of postrevolutionary hope, Libya splintered a few years later into two rival governments.

"What we found consistently over time is that air power is very effective, but air power is most effective when it is part of a joint force," said Kelly Grieco, an air power expert at the Stimson Center.

Air and ground

Part of what makes air power such a potent tool, she said, is that it prevents enemy forces from being able to concentrate safely, and when the enemy forces disperse, they lose their offensive power.

"That's why you often need your own ground forces or capable local partners, because they force the adversary to concentrate" so they become vulnerable targets for an air campaign, she said.

Even the strongest proponents of air power don't think it can single-handedly change the dynamics inside Iran, though they say it can establish an environment in which political change may occur by severely weakening the regime.

"You can take away all of those things that a state needs to be a threat to you and make it very difficult, and perhaps impossible for them to conduct future operations," retired Air Force Col. John Warden said in an interview.

"Now, if you want a new government to come in, somebody inside needs to do something to step up and actually take control."

Write to Michael R. Gordon at michael.gordon@wsj.com and Jared Malsin at jared.malsin@wsj.com

(END) Dow Jones Newswires

March 08, 2026 21:00 ET (01:00 GMT)

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