Tensions between Iran and the United States over Syria are at the highest they have been since the country’s civil war started in 2011.
While Tehran and Washington have repeatedly voiced indignation about the other’s presence in Syria, they have not reached the point of a military confrontation so far.
While the US has targeted fighters loyal to President Bashar al-Assad who have threatened its Kurdish allies and airbases, it has not directly attacked Iranian Revolutionary Guard Corps officers, who command both pro-Assad militias and are embedded with Syrian military units.
Similarly, while Iran has warned the US against intervening in Syria, it has not instructed the groups under its sway to target American forces.
In recent months, however, questions arose as to whether the US will continue its policy of non-confrontation with Iran in Syria.
In March, US President Donald Trump appointed John Bolton, a trenchant critic of Iran, as his new national security adviser.
A George W. Bush-era relic, best known as an advocate of the Iraq war, Bolton has reportedly lobbied Trump for a more aggressive posture on Iran.
The US ambassador to the UN, Nikki Haley, also fuelled concern about escalation when she said that preventing Iran’s entrenchment in Syria was one of the Trump administration’s top priorities.
Iran’s main regional rival, Israel, is said to have informed US intelligence officials before targeting Iranian positions in Syria, a sign of increasing cooperation between the two, according to the Wall Street Journal.
Militias backed by Iran for their part have vowed to target the US presence in Syria.
“What we are currently seeing is the most serious attempt by hawkish and conservative advisers to get the US directly involved in the Syrian war, an attempt that echoes Israeli concerns about US withdrawal plans from Syria,” said Joe Macaron of the Arab Center Washington, DC, further explaining that the aggressive position is not universally accepted.
“Trump himself and the Pentagon are resisting this temptation, Israel will most probably continue in the foreseeable future to fight its own battles against Iran.”
Despite the ratcheting up of threats, the idea of an all-out conflict between Tehran and Washington has little appeal to either, according to Scott Lucas, a professor of international politics at the University of Birmingham.
“There’s no appetite on either side to deliberately look for a wider conflict because then your costs outweigh your benefits,” he told Al Jazeera.
“You have to put in so many resources and have the problem of not knowing how far this will go,” Lucas added.
Instead, he said both Iran and the US seemed set to continue with a policy of pushing the envelope.
“There’s always the possibility of low-level conflict through people seeing how far they can go, but so far that hasn’t escalated into a wider military conflict,” he explained, giving the example of US attacks on Iranian-backed militias when they encroached on a US-controlled airbase near the Jordanian border in May 2017.
According to Lucas, while the US and Iran do not want war with each other at this moment in time, this does not mean they are not looking for other ways to negate each others’ influence in Syria.
He pointed to both countries having influence over effective fighting forces; Iran through its militias and the US through the Kurdish-dominated Syrian Democratic Forces (SDF).
Lucas added Washington could also pressurise Iran to limit its role in Syria through sanctions, while Tehran could seek exploitation of Syrian natural resources to counter any US punitive measures.
In the seven years since the start of the Syrian conflict, Iran has established deep roots within the country by commanding militias that count fighters in the tens of thousands.
The US has established influence in the country’s north, where the SDF rule, and in the south along the Jordanian border.
But the US public opinion has turned overwhelmingly against continued military intervention in Middle Eastern countries.
For some in Iran, there is a belief that the price of the US presence in Middle Eastern states cannot be sustained by Washington.
“Iran believes that a continued presence of American occupation forces in Syria is costly,” said Professor Mohammad Marandi of the University of Tehran.
“It angers Syrians, it makes the US vulnerable and ultimately it is not sustainable.”