In the early hours of June 22, 2025, local time, the United States attacked three nuclear facilities in Iran with “bunker buster” bombs and Tomahawk missiles.

Following more than a week of Israeli strikes on various targets in Iran – which had prompted retaliatory strikes from Tehran – the U.S. move marks a possible inflection point in the conflict. In initial comments on the strikes at the Fordo, Isfahan and Natanz facilities, President Donald Trump said that Iran’s nuclear program had been “completely and fully obliterated.” In response, Iran’s Foreign Minister Abbas Araghchi said the U.S. had “crossed a very big red line.”

The Conversation U.S. turned to Javed Ali, an expert on Middle East affairs at the University of Michigan and a former senior official at the National Security Council during the first Trump administration, to talk through why Trump chose now to act and what the potential repercussions could be.

What do we know about the nature and timing of US involvement?

President Trump has been forcefully hinting for days days that such a strike could happen, while at the same time opening up a window of negotiation by suggesting as late as June 20 that he would make a decision “within the next two weeks.” We know Trump can be very unpredictable, but he must have assessed that the current conditions presented an opportunity for U.S. action.

Trump met with the National Security Council twice in the days leading up to the strike. Typically at such meetings the president is presented with a menu of military options, which usually boil down to three: a narrow option, a middle ground and a “if you really want to go big” strike.

The one he picked, I would argue, is somewhere between the narrow option and the middle ground one.

The “go big” options would have been an attack on nuclear sites and Iranian leadership – be that senior members of Iran’s Revolutionary Guard, or possibly the Supreme Leader Ayatollah Ali Khamenei. The more narrow approach would have been just one facility, likely to have been Fordo – a deeply fortified uranium enrichment site buried within a mountain.

What did occur was a strike there, but also at two other sites – Isfahan and Natanz.

U.S. military chiefs confirmed that that 12 GBU-57s – the so-called 30,000-pound bunker busters – were dropped by B-2 bombers on Fordo, and two on Isfahan.

That suggests to me that the military goal of the operation was to destroy Iran’s ability to produce and or store highly enriched uranium in a one-time strike rather than drag the U.S. into a more prolonged conflict.

Has the strike achieved Trump’s objectives?

It will take some time to properly assess the extent to which Iran’s ability to produce or store highly enriched uranium has been damaged.

Certainly we know that the bombs hit their targets, and they have been damaged – but to what extent is not immediately clear. General Dan Caine, chairman of the Joint Chiefs of Staff, said that all three target sites had suffered “extremely severe damage and destruction” – possibly rolling back from Trump’s “fully obliterated” assessment. Perhaps most tellingly, Iran has not commented yet on the extent of the damage.

But to Trump, the objective was not just military but political, too. Trump has long said “no” to a nuclear Iran while at the same time has expressed that he has no desire to drag the U.S. into another war.

And this strike may allow Trump to achieve those seemingly contradictory goals. If U.S. initial assessments are correct, Iran’s nuclear program will have been severely compromised. But the strikes won’t necessarily pull U.S. into the conflict fully – unless Iran retaliates in such a way that necessitates further U.S. action.

And that is what Iran’s supreme leader and his military generals will need to work out: Should Iran retaliate and, if so, is it prepared to deal with a heavier U.S. military response – especially when there is no end in sight to its current conflict with Israel.

What options does Iran have to retaliate against US?

Iran has in the past tried to respond proportionately to any attack. But here is the problem for Iran’s leaders: There is no feasible proportionate response to the United States. Iran has no capability to hit nuclear plants in the U.S. – either conventionally or through unconventional warfare.

But there are tens of thousands of U.S. troops in the region, stationed in Iraq, Syria, the United Arab Emirates, Oman, Qatar and Jordan. All are in range of Iran’s ballistic, drones or cruise missiles.

But that military inventory has been depleted – both by using ballistic missiles in waves of attacks against Israel and by Israel hitting missile launch and storage sites in Iran.

Similarly, Tehran’s capacity to respond through one of its proxy or aligned groups in the region has been degraded. Hezbollah in Lebanon and Gaza’s Hamas – both of whom have ties to Iran – are in survival mode following damaging attacks from Israel over the past 18 months.

The Houthis in Yemen are in many ways the “last man standing” in Iran’s so-called “Axis of Resistance.” But the Houthis have limited capability and know that if they do attack U.S. assets, they will likely get hit hard. During Operation Rough Rider from March to May this year, the Trump administration launched over 1,000 strikes against the Houthis.

Meanwhile Shia militias in Iraq and Syria that could be encouraged to attack U.S. bases haven’t been active in months.

Of course, Iran could look outside the region. In the past the country has been involved in assassinations, kidnappings and terror attacks abroad that were organized through its Quds Force or via operatives of MOIS, its intelligence service.

But for Iran’s leaders, it is increasingly looking like a lose-lose proposition. If they don’t respond in a meaningful way, they look weak and more vulnerable. But if they do hit U.S. targets in any meaningful way, they will invite a stronger U.S. involvement in the conflict, as Trump has warned.

The parallel I see here is with the killing of Iranian general and commander of the Quds Force, Qassem Soleimani, in January 2020 by a U.S. drone strike.

On that occasion, Iran promised a strong retaliation. Its retaliatory attack against the U.S. Ain al-Asad air base in Iraq involved 27 ballistic missiles and caused the physical destruction of some of the facilities on base as well as traumatic brain injury-type symptoms to dozens of troops and personnel, but no deaths. Nevertheless, after this both the U.S. and Iran then backed off from deepening the conflict.

The circumstances now are very different. Iran is already at war with Israel. Moreover, the U.S. went after Iran’s crown jewels – its nuclear program – and it was on Iranian territory. Nonetheless, Khameini knows that if he retaliates, he risks provoking a larger response.

Trump suggested ‘further attacks’ could occur. What could that entail?

The U.S. has suggested that it has the intelligence and ability to hit senior leadership in Iran. And any “go big option” would have likely involved strikes on key personnel. Similarly there could be plans to hit the Iranian economy by attacking oil and gas targets.

But such actions risk either damaging the global economy or drawing the U.S. deeper into the conflict – it would evolve from a “one and done” strike to a cycle of attacks and responses. And that could widen political cracks between hawks in the administration and parts of Trump’s MAGA faithful who are against the U.S. being involved in overseas wars.

Is there any opportunity of a return to diplomacy?

Trump has not closed his “two weeks” window for talks – theoretically it is still open.

But will Iran come to table? Leaders there had already said they were not willing to entertain any deal while under attack from Israel. Araghchi, Iran’s foreign minister, said after the U.S. strikes that the time for diplomacy had now passed.

In any event, you have to ask, what can Iran come to the table with? Do they have much of a nuclear program anymore? And if not, what would they try to negotiate? It would seem, using one of Trump’s phrases, they “don’t have the cards” to make much of a deal.

Javed Ali does not work for, consult, own shares in or receive funding from any company or organization that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.