After weeks of tension, Trump is still talking tough on Iran. Here’s what could happen next

The prospect of a U.S. attack on Iran has roiled oil prices this year, but analysts tell CNBC a strike would require more military commitment and be more complicated, than the U.S. is prepared for.

Tensions are high, and despite talks last week in Oman, both sides remain at an impasse. U.S. President Donald Trump’s pressure on the Iranian regime escalated after a brutal crackdown on anti-government protestors across the country last month.

Trump said this week he was considering sending a second aircraft carrier to the Middle East, even as Washington and Tehran prepare to resume talks. On Tuesday, he threatened Iran with “something very tough,” if it does not agree to Washington’s demands, which range from halting the country’s nuclear enrichment to cutting Tehran’s ballistic missile program.

The U.S. deployed the USS Abraham Lincoln carrier strike group to the Middle East in January. This brought the number of missile destroyers in the region to six, but, analysts say, this still wouldn’t be enough to topple the regime. Following through on his “something tough” threat would mean a prolonged conflict in a region Trump is wary of.

“U.S. forces in the region are not adequate to support a significant long-term military operation in Iran which would be necessary to achieve any major military objective,” Alireza Ahmadi, executive fellow at the Geneva Center for Security Policy, told CNBC.

Trump has also dialed up his pressure on the Islamic Republic, applying financial pressure to an economy already crippled by sanctions. Just last month, he vowed to impose tariffs on any country that acquires any goods or services from Iran.

But it is unclear what could come next. “President Trump is notoriously unpredictable,” Ali Vaez, director of Iran Project at Crisis Group, told CNBC but added Trump is aware “the Iran problem set does not lend itself to clean and easy military options.”

Michael Rubin, a former Pentagon official and senior fellow at the American Enterprise Institute, told CNBC that “the cost of not attacking Iran would be huge,” adding, if he doesn’t, “Trump’s legacy will be as the president who enabled Iran to go nuclear.”

“The President is in a jam, his options are not great and it’s a very risky moment at this point,” Bob McNally, president of Rapidan Energy Group, told CNBC’s Dan Murphy last week. McNally added the country’s ballistic missile program meant that “we’d have to go big, because Iran is quite formidable.”

Trump said last week that Iran’s supreme leader, Ayatollah Khamenei, should be “very worried.”

But targeting Iran’s leadership would not be an operation like the one that seized Venezuelan President Nicolas Maduro, analysts have warned.

“The Iranian government is not Venezuela,” Alireza Ahmadi said, adding that if the U.S. removed Khamenei, “a replacement would be chosen immediately and the military would effectively be running the country for the foreseeable future.”

Power in Iran is centralized around Khamenei. While there is a president, the Islamic Republic’s political, military and foreign policy decisions are all made by him. Khamenei has held ultimate authority for the last three decades, aided by the Iranian Revolutionary Guard Corps, which helps enforce the regime’s policies and plays a major role in its foreign policy.

If the U.S. were able to remove Khamenei and found a regime official to replace him with, there would still be an “open question” on what happens to the IRGC, Rubin told CNBC.

“The U.S. cannot change the regime through air power alone and without any boots (U.S. or Iranian) on the ground. It can only transform the regime into something else, which could be worse, or turn Iran into another failed state,” Vaez told CNBC.

Ahmadi said regime change in Iran “would require at least an Iraq War level of military commitment, which Trump is unlikely to favor.” Between 2003 and 2011, 4,500 American armed forces personnel were killed in Iraq.

The White House claimed after strikes on three main nuclear sites last year that Iran’s nuclear facilities were “obliterated.” Iran moved to quickly repair the damage to ballistic missile sites but according to analysis from the New York Times, has made “limited fixes” to the major nuclear sites hit by the United States.

Iran has long claimed it does not have any plans to develop nuclear weapons. As talks restart between Washington and Tehran, Iran has offered to cap its enrichment at low levels. The U.S. has opposed the Iranians enriching any uranium since the nuclear deal collapsed in 2018.

While the U.S. has vowed to attack Iran if it resumes its nuclear and missile programs, it is unclear whether these sites would again be primed for attack. “Both options are likely to lead to a disproportionate Iranian retaliation, which could then turn the confrontation into a regional conflagration,” Vaez said.

Iran has vowed to retaliate against U.S. bases in the region if Washington strikes.

“Iran is betting that the U.S. does not have enough missile interceptors and THAAD systems to protect its sprawling military bases and facilities across the region, as well as Israel,” Ahmadi told CNBC.

The U.S. has around 40,000 military personnel in the Middle East. It has bases in the Arabian Gulf including the United States Naval Forces Central Command in Bahrain, Al Udeid air base in Qatar, which Iran hit last summer and Al Dhafra air base just south of Abu Dhabi.

“Iran will undoubtedly target U.S. bases in Iraq, Syria, the Gulf, and its naval assets. It is also likely to target Israel. The remnants of its proxies could also join in,” Vaez told CNBC.

Iran seems “to be preparing for a week, if not months, long military confrontation. There seems to be a sense among Iranian leadership that the U.S. is overestimating its leverage and that a significant war may be necessary to correct those assumptions,” Ahmadi added.