Regime change, all-out war or a nuclear deal: What could happen if Trump strikes Iran?

The US president has renewed threats against Iran, weeks after promising to come to the aid of anti-government protesters

Donald Trump has renewed his threat of military action against Iran, urging the Islamic Republic to make a ‘deal’ or face the consequences with a “massive armada” already en route to the region.

The US president said on Wednesday that time was running out for Tehran to avoid a repeat of last summer’s strikes against the country’s nuclear facilities, warning this time would be “far worse”.

The U.S. has been seeking a deal to curb Iran’s nuclear programme even after claiming to have totally destroyed it in a bombing campaign last June. However, officials fear the programme was not destroyed and that the regime has been reconstituting it. Iran denies trying to make a bomb, but says it is open to talks.

The decision to move a carrier strike group to the region gives Trump a wider range of options than he had earlier this month, when he vowed to come to the rescue of anti-government protesters being brutally killed and targeted by the regime.

But U.S. bases and partners in the region will be fearing an Iranian retaliation after regime officials threatened an ‘unprecedented’ response if provoked. The Independent looks at what is likely to happen next in Iran.

A US fighter jet is prepared on the deck of an aircraft carrier en route to the Middle East (AP)

Military intervention

Trump has been deliberating how to attack Iran for weeks, according to officials. But the range of options — from a coordinated cyber attack to strikes on nuclear facilities — has been limited by the recent dispersal of U.S. military assets around the world.

Washington has fewer options than it did when it struck key Iranian sites last summer, using B-2 bombers from Missouri alongside 125 military aircraft, decoys in the Pacific and missiles from a submarine. But the arrival of the Abraham Lincoln carrier strike group — flanked by destroyers and housing up to 65 aircraft — lends credibility to his recent threat.

The US could use limited strikes against military bases and nuclear sites to press Iran to make a deal. This would limit civilian casualties, but could also see Iran try to save face with limited retaliatory strikes against US bases in the region.

With recent memory of Iran hitting back at Israel and the U.S. base in Qatar last year, Saudi Arabia and the U.A.E. said this week they would not let the U.S. use their airspace or territory to attack Iran, limiting options.

Iran fired salvoes of missiles at Israel last summer at the height of tensions (AP)

Iran striking back hard

Ali Shamkhani, an adviser to Iran’s supreme leader, said a U.S. attack on Iran would warrant an “unprecedented” response against the U.S. and Israel.

“Any military action by ‌#us—from any origin and at any level— will be considered the ‌#start_of_war⁩, and its response will be immediate, ‌#all_out⁩, and unprecedented, targeting heart of ‌#TelAviv⁩ and all those supporting the aggressor. [sic]” he wrote on X this week.

Experts say Iran may not have the resources to prosecute a major regional war, but will likely be forced into a response. Last June, Tehran launched missiles at a U.S. military base in Qatar in response to a joint U.S.-Israeli bombing campaign. All of the missiles were intercepted and there was no casualties.

Last year, the U.S. sent B-2 bombers (pictured) from Missouri to strike Iran, backed by dozens of planes and missiles launched from a submarine (AFP/Getty)

Karim Sadjadpour of the Carnegie Endowment for International Peace told the Wall Street Journal: “Both Saudi and the U.A.E. have been targets of attacks by Iran and their proxies. A degraded and less threatening Iranian regime is in their interests, but they worry about regional unrest and Iranian retribution and don’t want to be the tip of the American spear.”

This time, the U.S. is believed to have far fewer interceptor missiles needed to respond to an attack. In July, The Guardian reported that the U.S. only had around 25 per cent of the Patriots it needed after depleting stockpiles.

“If it does become a longer-term volley of strikes, then your interceptor capacity becomes all the more important,” a former defence official told Politico. “We could get in a sticky situation very quickly on that front.”

Regime change

US secretary of state Marco Rubio assessed on Wednesday that the Iranian regime was probably weaker than it had ever been. His comments follow the most serious protests against Tehran in years over the country’s deep economic crisis.

Multiple sources told Reuters that Trump was weighing strikes that would aim to inspire protesters and create the conditions for regime change.

But setting out to topple the regime would be a costly and uncertain venture for the U.S., experts say.

Arab officials and Western diplomats told Reuters they were concerned that instead of bringing people onto the streets, U.S. strikes could weaken a movement already in shock after the bloodiest repression by authorities since the 1979 Islamic Revolution.

Alex Vatanka, director of the Iran Program at the Middle East Institute, said that without large-scale military defections Iran's protests remained “heroic but outgunned.”

Trump has also notably avoided endorsing a successor, and Iran’s exiled crown prince Reza Pahlavi lacks sufficient support within the country to immediately be installed as leader.