Even before the drone strike that killed three U.S. service members in Jordan on Sunday, the Biden administration was planning for a moment just like this, debating how it might strike back in ways that would deter Iran’s proxy forces and send a message that Iran would not miss.

But the options range from the unsatisfying to the highly risky.

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President Joe Biden could order strikes on the proxy forces, a major escalation of the whack-a-mole attacks it has conducted in recent weeks in Syria, Iraq and Yemen. So far, those attacks have put a dent into the abilities of the Iranian-backed groups that have mounted more than 160 attacks. But they have failed, as Biden himself noted 10 days ago, to deter those groups.

U.S. President Joe Biden.

Biden could decide to go after the Iranian suppliers of drones and missiles, perhaps including inside Iranian territory, which poses a much higher risk. His first targets could well be members of Iran’s Revolutionary Guard, many of whom are based in Syria and Iraq. Depending on how these strikes are conducted, it could open another front in the war, with a far more powerful adversary, and trigger Iran to accelerate its nuclear program.

In short, it would force Biden to do everything he has been trying so far to avoid.

There are options in between, officials say, and strikes could be combined with back-channel messaging to the Iranians that they should absorb the hit and not escalate. Such signaling has been successful before, including after the U.S.-ordered killing of Qassem Soleimani, the head of its powerful Quds Force, in 2020. Then, as now, there were fears of an all-out war in the Middle East that would pit the United States and its allies against Iran and its proxies. Both sides backed away.

But the brew of political pressures, military calculations and regional fragility is quite different today from four years ago, even though evidence suggests that Iran does not want to engage directly in war either, especially when its own economy is weak.

“There are no good choices, but the deaths and wounds of so many U.S. troops and SEALs demand a strong response,” said James Stavridis, a retired Navy admiral who now works for the Carlyle Group, a global investment firm.

“A multiday air campaign against all proxies, coupled with a ‘last chance warning’ to Iran is warranted,” he said. “The Pentagon should be creating options that go directly against Iranian weapons production facilities, naval assets and intelligence systems in case the mullahs want to go another round. A strong offensive cyberattack would be another viable option, either alone or in conjunction with kinetic strikes.”

Because Iran has been an adversary for so long, across eight presidencies, there is no shortage of such options. The United States has identified the major drone-making factories, and their overseas suppliers, that are fueling the Russian attacks in Ukraine and supplying Hezbollah, the Houthis and other proxy groups. (It is not yet clear whether the drone, or drones, that killed the Americans in Jordan on Sunday were Iranian made, but that was the working assumption of U.S. officials.)

U.S. forces have mapped out strikes on Iranian missile sites and air bases in case a conflict broke out between Iran and Israel. There was even a detailed cyberattack option against Iran, code-named “Nitro Zeus,” to disable Iran’s air defenses, communications systems and crucial parts of its power grid. That plan was shelved in 2015 after Iran and six other nations struck a nuclear deal. Israel has conspicuously practiced bombing runs, simulating attacks on the Natanz nuclear enrichment site and its deep-underground alternative site, called Fordow.

But no one pulled the trigger on these plans for a reason: Neither the U.S. nor Iran could see a way out of the cycle of strikes and counterstrikes once an all-out conflict began. And while U.S. officials were certain the United States would ultimately prevail, the potential for damage done to U.S. allies, particularly Israel, seemed hard to imagine. Even President Donald Trump pulled back from a planned strike.

None of those considerations was reflected in the social media posts and news releases issued Sunday by Republicans who have criticized Biden’s responses so far as too calibrated. The Senate minority leader, Mitch McConnell of Kentucky, called for “crippling costs” for Iran, “not only on front-line terrorist proxies, but on their Iranian sponsors who wear American blood as a badge of honor.” Sen. John Cornyn, R-Texas, demanded strikes on the Revolutionary Guard, its military elite — and the guardians of the nuclear program.

“Time to kill another Iranian general, perhaps?” Rep. Daniel Crenshaw, also of Texas, wrote on social media Sunday, recalling the Soleimani attack. “That might send the right message.” Crenshaw is a veteran of Iraq and Afghanistan, where he lost an eye in a blast.

Such calls have an undeniable political appeal, especially at the start of an election year, and no one was more vocal than Trump — who made no mention of his own qualms about killing Iranians and escalating a conflict when he was in office. Even Biden’s own aides acknowledge that whatever they have been doing so far to “restore deterrence,” to use the military’s phrase about their effort, has failed at the objective.

But it is not yet clear who, exactly, Biden aims to deter. U.S. intelligence officials say that while Iran provides weapons, funding and sometimes intelligence to its proxy groups, there is no evidence that it calls the shots — meaning it may not have known in advance about the attack in Jordan.

The Iran-backed militias that call themselves the Axis of Resistance claimed responsibility for the attack on the outpost in Jordan, saying it was a “continuation of our approach to resisting the American occupation forces in Iraq and the region.”

A spokesperson for Iran’s Foreign Ministry, Nasser Kanaani, said at a news conference in Tehran, Iran, on Monday that the militias “do not take orders” from Iran and act independently. It is a convenient argument, one that preserves some sense of deniability for Iran.

But the speed at which Iran tried to distance itself from the strike, rather than embrace it, underscored that the downside of using proxies is the same as the upside: Iran will be blamed for everything the militias do, even acts the Iranians believe are too provocative.

“This is the inherent risk in Iran’s proxy-war strategy,” said Ray Takeyh, an Iran expert at the Council on Foreign Relations. “It has been brilliantly successful, but only if the retaliation focuses on proxies and not on Iran’s own territory. Now there is a real risk of things getting even more out of hand in the region.”

Biden is running out of middle-ground options. Sanctions have been exhausted; there is barely a sector of the Iranian economy that the United States and Europe are not already punishing, and China continues to buy up Iranian oil. He could approve “strike packages” against a variety of proxies, but that would embolden some of them, and give some of them the status they crave as legitimate U.S. enemies.

And, following Stavridis’ suggestion, it could look to cyberattacks, more stealthy, deniable ways to make a point. But the lesson of the past decade of cyberconflict with Iran — in both directions — is that it looks easier in the movies than in reality. Gaining access to critical networks is hard, and having lasting impact is even harder. The most famous American-Israeli cyberattack on Iran, aimed at its nuclear centrifuges 15 years ago, slowed the nuclear program for a year or two but did not put it out of business.

And that is Biden’s challenge now: In the middle of an election, with two wars underway, he needs to put Iran’s sponsorship of attacks on Americans out of business — without starting another war.

Political pressure builds on Biden to strike Iran after US deaths

The killing of three U.S. troops and wounding of dozens more on Sunday by Iran-backed militants is piling political pressure on President Joe Biden to deal a blow directly against Iran, a move he's been reluctant to do out of fear of igniting a broader war.

Biden's response options could range anywhere from targeting Iranian forces outside to even inside Iran, or opting for a more cautious retaliatory attack solely against the Iran-backed militants responsible, experts say.

American forces in the Middle East have been attacked more than 150 times by Iran-backed forces in Iraq, Syria, Jordan and off the coast of Yemen since the Israel-Hamas war erupted in October.

But until Sunday's attack on a remote outpost known as Tower 22 near Jordan's northeastern border with Syria, the strikes had not killed U.S. troops nor wounded so many. That allowed Biden the political space to mete out U.S. retaliation, inflicting costs on Iran-backed forces without risking a direct war with Tehran.

Biden said the United States would respond, without giving any more details.

Republicans accused Biden of letting American forces become sitting ducks, waiting for the day when a drone or missile would evade base defenses. They say that day came on Sunday, when a single one-way attack drone struck near base barracks early in the morning.

In response, they say Biden must strike Iran.

"He left our troops as sitting ducks," said Republican U.S. Senator Tom Cotton. "The only answer to these attacks must be devastating military retaliation against Iran's terrorist forces, both in Iran and across the Middle East."

The Republican who leads the U.S. military oversight committee in the House of Representatives, Representative Mike Rogers, also called for action against Tehran.

"It's long past time for President Biden to finally hold the terrorist Iranian regime and their extremist proxies accountable for the attacks they've carried out," Rogers said.

Former President Donald Trump, who hopes to face off against Biden in this year's presidential election, portrayed the attack as a "consequence of Joe Biden's weakness and surrender."

The Biden administration has said that it goes to great lengths to protect U.S. troops around the world.

One Democrat openly voiced concern that Biden's strategy of containing the Israel-Hamas conflict to Gaza was failing.

"As we see now, it is spiraling out of control. It's beginning to emerge as a regional war, and unfortunately the United States and our troops are in harms way," Democratic Representative Barbara Lee said, renewing calls for a ceasefire in the Israel-Palestinian war.

NOT SO SIMPLE

Democratic Representative Seth Moulton, who served four tours in Iraq as a Marine, urged against Republican calls for war, saying "deterrence is hard; war is worse.”

"To the chicken hawks calling for war with Iran, you're playing into the enemy's hands—and I’d like to see you send your sons and daughters to fight," Moulton said. "We must have an effective, strategic response on our terms and our timeline."

Experts caution that any strikes against Iranian forces inside Iran could force Tehran to respond forcefully, escalating the situation in a way that could drag the United States into a major Middle East war.

Jonathan Lord, director of the Middle East security program at the Center for a New American Security, said striking directly inside Iran would raise questions for Tehran about regime survival.

"When you do things overtly you represent a major escalation for the Iranians," Lord said.

Charles Lister of the Washington-based Middle East Institute said a likely response would be to go after a significant target or high-value militant from Iran-backed groups in Iraq or Syria.

"What happened this morning, was on a totally different level than anything these proxies have done in the past two to three months... (but) despite all of the calls to do something in Iran, I don't see this administration taking that bait," Lister said.

A U.S. defense official, speaking on the condition of anonymity, said it was unclear what the second and third order effects would be in going after Iran.

"Unless the U.S. prepared for an all out war, what does attacking Iran get us," the official said.

Still, Lord and other experts acknowledge that Israel had hit Iranian targets in Syria for years, without dissuading Iran, including four Iranian Revolutionary Guard Corps officials in Damascus on Jan. 20.

The United States has also struck Iranian-linked targets outside of Iran in recent months. In November, the U.S. military said it struck a facility used not only by Iran-backed group but also by the Iran's Revolutionary Guard Corps.

But Lister said the U.S. had gone after Iranians outside of Iran in the past, like the 2020 strike against top Iranian general Qassem Soleimani, and only yielded a response during a limited period of time.

"So to an extent, if you go hard enough and high enough, we have a track record of showing that Iran can blink first," Lister said.

Iran may not have been seeking to trigger a regional war with the drone strike that killed 3 US troops, say experts.

• 3 US soldiers were killed in an attack on a US base in Jordan on Sunday.

• Some analysts believe the attack may not have been a deliberate escalation by Iran.

• President Joe Biden has pledged revenge for the drone strike.

The Middle East appeared to have moved closer to a regional war on Sunday after three US troops were killed and dozens more were injured in an attack on a US base in Jordan.

The drone attack was launched by the Islamic Resistance, an Iran-backed militia based in Iraq. It seemed to many analysts to signify an escalation in Iran's aggression toward the US and its allies in the region.

However, several experts are warning against such a conclusion, claiming that Iran may not have been seeking to trigger an escalation in the conflict.

On the brink of war

President Joe Biden pledged revenge for the drone strike, and early Monday Iranian-linked targets in Syria were struck, though it's unclear who was behind the attacks.

"We had a tough day last night in the Middle East," he said. "We lost three brave souls in an attack on one of our bases, and we shall respond."

The Middle East has been on the brink of wider war since October 7, 2023, when the Iran-backed Hamas militant group killed around 1,200 Israelis in terror attacks. Israel invaded Gaza in response, and conflict escalated between Israel's and Iran's allies.

Tobias Borck, an analyst on Middle Eastern security at the Royal United Services Institute, told Business Insider that Iran-backed groups in the region had been intensifying their attacks since then.

The longer the attacks continue, he said, the more the risk of casualties increases.

"You're going to kill people eventually," he said of Iran, pointing to the fact that Iran-backed groups had launched 150 attacks on US bases since last October.

Greg Brew, an Iran analyst for the Eurasia Group, echoed that assessment, commenting on X: "It doesn't track that #Iran would allow its allies in Iraq to launch 200+ attacks on US forces for three months without some expectation that it would cause US casualties."

And The New York Times reported that US officials are trying to establish if the attack was a deliberate escalation or the same kind of attack the US has faced for months that managed to get through by luck.

Some analysts are also questioning why the drone, which struck a logistics support base, wasn't intercepted by US air defenses, which have prevented hundreds of other attacks that could have resulted in casualties.

A US official said that the drone was approaching the base at the same time as a US drone was expecting to return, meaning air defense systems were switched off, according to a US defense official cited by CBS.

Borck said without more data on the specific type of drone and technology used, it was impossible to say if the militia anticipated the likelihood of the attack evading air defenses.

US struggles to deter Iran

US attempts to deter Iranian proxies have so far been met with little success.

Despite being targeted by waves of US and UK airstrikes, Houthi militants in Yemen have continued to attack ships in the Red Sea, setting fire to an oil tanker last week. US airstrikes on Iran-linked militia bases in Iraq did not deter the Jordan attack.

With a presidential election approaching, Iran is likely calculating that Biden is keen to avoid becoming entangled in a massive regional conflict, emboldening its allies to continue attacking US targets.

However, Biden is already being criticized by Republicans for being too cautious in responding to Iranian aggression, and the president will have to respond to the airbase strike in a way that's emphatic enough to silence domestic critics, Robert Dover, a professor focussed on international security at the University of Hull told BI.

His key decision will be whether to launch attacks on Iranian targets outside the country, or in Iran itself, treading a balance between sending a clear message to Tehran and not causing the conflict to spiral out of control.

"The geopolitical landscape for this president has become an awful lot more hazardous overnight," Dover said.