As the Trump administration enters its sixth month, fears that it would unilaterally rip up its predecessor’s landmark Iran nuclear agreement are beginning to fade.

But the chances for confrontation between the United States and the Islamic Republic remain worrisomely high as the two sides test each other’s defenses and proxies in regional conflicts. Any significant loss of American life as a result of Iranian actions could lead to a wider war — or at minimum, undercut the Trump administration’s willingness to continue to renew the necessary waivers that underpin the Joint Comprehensive Plan of Action (JCPOA).

Syria is a likely, but not the only, possible venue for a clash, with large areas of its eastern desert literally up for grabs as a US-led coalition squeezes out the Islamic State (ISIS) from the Euphrates Valley.

On May 18, the US bombed Iran-backed forces that had advanced into a “de-confliction zone” surrounding US-led forces near the town of al-Tanf. Then, twice in June. US forces shot down armed Iranian drones near al-Tanf, which sits on one of three main border crossings between Iraq and Syria and is also adjacent to Jordan. American and Jordanian forces have been working with Syrian Sunni rebels in the region for several years and see these proxies as key both to defeating ISIS and to preventing Iran from establishing a land bridge between Tehran and Beirut via the highway that connects Baghdad and Damascus.

In the first incident, on June 8, the Shahed 129 drone had already dropped a bomb near US-backed forces but fortunately caused no casualties. In the second, on June 20, a US F-15E fighter jet destroyed the drone before it could strike.

Iran has also fired ballistic missiles at ISIS targets in Syria in apparent retaliation for rare terrorist attacks in Tehran that killed at least 18 people. And the US has shot down a Syrian fighter jet that reportedly came too close to US-backed personnel. In April, meanwhile, the US sent Tomahawk cruises missiles to hit a Syrian airfield in the western part of the country in response to a reported chemical weapons attack on Syrian civilians. The Trump administration threatened similar action again this week.

These actions are taking place in a context of what appears to be strategic uncertainty in the Trump administration regarding both Syria and Iran. An “Iran review” has been proceeding for months with no end in sight. Meanwhile in Syria, while the US-led coalition is having increasing success against ISIS, there is no evident plan for what happens after ISIS is defeated.

US officials speak vaguely of empowering local Sunni actors and avoiding an on-the-ground role in the Syrian civil war. But Iran-backed Iraqi Shi’ite militias have already linked up with counterparts in Syria. Iran’s track record of grooming proxies and partners – honed over four decades – has been far more successful than episodic US attempts. Iran’s alliance with the Assad regime goes back to 1980 when Syria was the only Arab country to side with Iran after it was invaded by Saddam Hussein’s Iraq. After the beginning of a popular uprising against Bashar al-Assad’s government in 2011, Turkey and some Sunni Arab states backed the opposition in hopes of removing Assad and avenging the US toppling of Iraq’s Sunni dictatorship in 2003. But Assad, backed by Iran-trained militias and Russian airpower, has clawed back control of most of western Syria and now seems intent on recapturing the rest.

Further complicating the picture is political factionalism in both Washington and Tehran. In the US, Republican neoconservatives such as Sen. Tom Cotton of Arkansas have openly called for regime change in Iran. Among those dealing with Iran on the White House National Security Council are former US Army officers who remember losing comrades to Iran-backed militias in Iraq a decade ago and appear essentially predisposed to blame Iran for almost every crisis in the Middle East. So far, Defense Secretary James Mattis seems to have rebutted their more boneheaded schemes but it would be harder for Mattis to do so in the event of US casualties linked to Iran (perhaps even in his own mind).

Even Secretary of State Rex Tillerson, who has chosen not to side with Saudi Arabia in that country’s current ill-advised feud with Qatar, has told a Congressional hearing that he would like to see a “peaceful transition” of government in Iran, presumably in favor of one less hostile to the United States and Israel.

These statements have been coupled with new sanctions in Congress tied to Iran’s testing of ballistic missiles. There has also been a shriveling of people-to-people ties with Iran in the wake of Trump’s assorted travel bans — elements of which were just temporarily reinstated by the Supreme Court.

In Iran, the hostile US rhetoric, travel restrictions and new sanctions are a gift to hardliners, especially the commanders of the Islamic Revolutionary Guard Corps (IRGC) and Supreme Leader Ayatollah Ali Khamenei, whose power is based in part on portraying the United States as a hegemonic bogeyman determined to overthrow the Iranian government and dominate the Persian Gulf.  Hardliners argue that the United States has never accepted the legitimacy of Iran’s 1979 revolution because it made Iran an independent actor in the Middle East.

The regime change remarks and new sanctions also undercut Iran’s newly re-elected President Hassan Rouhani. It was during his first term that Iran, the US and five other powers successfully negotiated the JCPOA, which puts verifiable curbs on Iran’s nuclear program for more than a decade.  Rouhani promised that the deal would lead to significant economic growth and has sought to attract trade and direct investment from Western nations. A new crisis with the United States would frighten off Western firms, oblige Rouhani to take a more nationalistic stance and weaken his ability to enact economic reforms.

Already, Rouhani is encountering a significant backlash from hardline clerics and others disappointed by the poor showing of their candidate, Ebrahim Raisi. There have been ominous comparisons of Rouhani with Iran’s first president, Abolhassan Banisadr, who was forced to flee Iran in 1981 after he was impeached in a bitter factional fight and accused of being too soft on the United States.

Rouhani has extensive popular as well as institutional support and benefits from Iranians’ ambivalence about their country’s costly military adventures in Arab states. But if US forces take Iranian lives on one of these battlefields, Rouhani will have to align himself firmly with the Supreme Leader and the IRGC.

Syria has been most in the news, but it is not the only place where American and Iranian forces could come to blows. There have been dozens of unsafe interactions between IRGC speedboats and US ships in the narrow waters of the Persian Gulf. Establishing a hot line to prevent an armed clash has been a perennial request of US Centcom commanders, but Iran has so far not agreed.

There could also be an incident off the coast of Yemen where Iran-backed Houthi rebels have attacked Saudi ships. It is also still uncertain whether the Saudi-led coalition, with or without direct US support, will mount a massive assault on the northwest port of Hudaydah, which is currently under Houthi control.

Afghanistan is yet another possible venue for Iran-US confrontation. Iran has increased its ties with elements of the Taliban as a way of countering ISIS and also gaining leverage against the US, which is increasing the number of American troops there. It is not inconceivable that Iran would retaliate against Americans in Afghanistan — or Iraq — for an incident in which it lost personnel in Syria.

All of this is taking place at a time when US-Iran diplomatic channels have atrophied. Tillerson – unlike John Kerry – does not have Iranian Foreign Minister Javad Zarif on speed dial. The only remaining avenue for US-Iran talks is the Joint Commission created by the JCPOA to deal with implementation of the nuclear agreement. It meets only every few months.

So at present, officials in the US and Iran are insulting each other from a distance while rubbing uncomfortably close in the battlefields of the Middle East and South Asia. What could conceivably go wrong? Unfortunately, a whole lot with no one the winner.


Image: The Security Council unanimously adopts resolution endorsing the Joint Comprehensive Plan of Action and establishing a monitoring system for Iran’s nuclear program, July 20, 2015 UN Photo