Explained: Iranian-linked Strike Kills US Contractor In Syria, US Responds With Airstrikes, What's It All About?

Following Iran-linked drone attack that killed a US contractor and injured six more Americans deployed in Syria, the United States launched its own strikes and vowed a "forceful" response.

On Thursday, a drone strike at a US military base in Syria killed one US contractor and injured a second contractor and five US soldiers. The United States responded with strikes on groups affiliated with the Iran Revolutionary Guards Corps (IRGC), the personal sword arm of the Supreme Leader of Iran. A report says four persons were killed in US strikes. 

The exchange of strikes between the United States and Iran-linked militia have raised the US-Iran tensions at a time when bilateral relationship is already at a very low point and Iran is working to normalise relations in the region. 

Following the strikes, US President Joe Biden said the United States would respond "forcefully" to protect its personnel after US forces retaliated with airstrikes on sites in Syria used by groups affiliated with IRGC. 

"The United States does not, does not seek conflict with Iran," said Biden in Canada's Ottawa, where he is on a state visit. But he said Iran and its proxies should be prepared for the United States "to act forcefully to protect our people. That's exactly what happened last night". 

Here we explain what we know so far of the exchange of strikes, how it escalates the tensions, and what the US personnel are doing in Syria. 

What we know of US-Iran strikes?

Syria is divided between areas controlled by Bashar al-Assad's government and the rebels and Kurds opposed to him. The US forces are stationed in areas outside of Assad's government control. Iran-linked militias are also active in the region. 

On Thursday, one US contractor was killed, a second contractor was injured, and five US soldiers were also injured in a drone strike at a base near Hasakah in northeastern Syria. 

The US Department of Defense (DoD) said in a statement that Iran-backed militants were responsible for the strikes. The DoD statement further said that the US response included F-15 fighter planes bombing Iran-linked militants in the region.

"The airstrikes were conducted in response to yesterday's attack, as well as a series of recent attacks against coalition forces in Syria by groups affiliated with the IRGC...Initial indications are that the facilities were destroyed. These precision strikes were intended to protect and defend US personnel, and the US took proportionate and deliberate action intended to limit the risk of escalation and minimise casualties," said Pentagon Press Secretary Air Force Brig. Gen. Pat Ryder on Friday. 

Overnight, videos on social media purported to show explosions in Syria's Deir el-Zour, a strategic province that borders Iraq and contains oil fields. Iran-backed militia groups and Syrian forces control the area, which also has seen suspected airstrikes by Israel in recent months allegedly targeting Iranian supply routes.

The activist group Deir Ezzor 24 put the death toll from the American strikes at four people. Deir Ezzor 24, which covers news in Deir el-Zour province, said the strikes hit the city of Deir el-Zour as well as militiamen posts near Mayadeen and Boukamal. It said the strikes also wounded people, including Iraqis. 

The Syrian Observatory for Human Rights, an opposition war monitor, reported that the American strikes killed six Iranian-backed fighters at an arms depot in the Harabesh neighbourhood in the city of Deir el-Zour. It said US bombing at a post near the town of Mayadeen killed two fighters.

A separate American strike hit a military post near the town of Boukamal along the border with Iraq, killing another three fighters, the Observatory said.

The AP could not immediately independently confirm the activist reports. 

The Iran-linked militia responded with another round of strikes. The officials said that based on preliminary information, there was a rocket attack Friday at a Conoco plant, and one U.S. service member was injured but is in stable condition. At about the same time, several drones were launched at Green Village, where U.S. troops are also based. One official said all but one of the drones were shot down, and there were no U.S. injuries there. The officials spoke on condition of anonymity to discuss military operations.

The long tense US-Iran relationship

With the latest round of strikes, the already-tense US-Iran tensions have witnessed a further nose-dive. The United States and Iran do not have diplomatic missions and have an adversarial relationship that has worsened in recent years over the Iran's nuclear program, its destabilising campaign in the Middle East, and its support to Russia in the Ukraine War with weaponry.

Iran is subject to a wide range of economic sanctions over its nuclear program. However, the US-Iran tensions go decades back to 1979 when the Islamic Revolution of Iran overthrew the pro-West liberal monarchy and replaced it with a hardline Islamic state. Soon, the Islamic activists laid siege to the US embassy and held diplomats and staff hostage. Fifty-two US citizens were held hostage inside the embassy for over a year. 

While it's not the first time the United States and Iran have traded strikes in Syria, the attacks and the U.S. response threaten to upend recent efforts to deescalate tensions across the wider Middle East, whose rival powers have made steps toward détente in recent days after years of turmoil.

US-Iran strikes come amid peace efforts

The exchange of strikes came as Saudi Arabia and Iran have been working toward reopening embassies in each other's countries. The kingdom also acknowledged efforts to reopen a Saudi embassy in Syria, whose embattled President Bashar Assad has been backed by Iran in his country's long war.

According to officials, Iran has launched 80 attacks against U.S. forces and locations in Iraq and Syria since January 2021. The vast majority of those have been in Syria.

Diplomacy to deescalate the exchange appeared to begin immediately. The foreign minister of Qatar spoke by phone with U.S. National Security Adviser Jake Sullivan as well as Iranian Foreign Minister Hossein Amirabdollahian, the Qatari state news agency reported. Doha has been an interlocutor between Iran and the U.S. recently amid tensions over Tehran's nuclear program.

The U.S. under Biden has struck Syria previously over tensions with Iran — in February and June of 2021, as well as August 2022.

Dareen Khalifa, a senior Syria analyst with the Brussels-based International Crisis Group, said that while Thursday's exchange of strikes comes at a sensitive political moment due to the “overall deterioration of U.S.-Iran relations and the stalling of the nuclear talks,” she does not expect a significant escalation.

“These tit-for-tat strikes have been ongoing for a long time,” Khalifa said, although she noted that they usually do not result in casualties.

Since the U.S. drone strike that killed Revolutionary Guard Gen. Qassem Soleimani in 2020, Iran has sought “to make life difficult for U.S. forces stationed east of the Euphrates,” said Hamidreza Azizi, an expert with the German Institute for International and Security Affairs.

“Iran increased its support for local proxies in Deir el-Zour while trying to ally with the tribal forces in the area,” Azizi wrote in a recent analysis. 

The strikes come during the Muslim holy month of Ramadan.

Why are US personnel deployed in Syria?

The US service personnel along with contractors are deployed in Syria primarily for counter-terrorism purposes and combating Iranian influence in the region. 

Syria and large parts of neighbouring Iraq were under they physical control of terrorist group ISIS. Though the Caliphate of the ISIS was defeated in 2019, the terrorist group continues to pose a threat and US personnel along with regional partners work to prevent its resurgence and carry out operations against its leadership time to time.

On any given day there are at least 900 U.S. forces in Syria, along with an undisclosed number of contractors. U.S. special operations forces also move in and out of the country, but are usually in small teams and are not included in the official count. The US personnel have been deployed there since 2015.

U.S. forces advise and assist the SDF, including in securing the detention facilities, and they also conduct counterterror missions against the Islamic State group and other al-Qaida-affiliated militants, and carry out strikes on Iran-backed militias that have attacked U.S. facilities.

Russia, an ally of the Syrian government, is also active in the country, but Washington and Moscow have used a deconfliction phone line in an effort to avoid conflict there.

Tehran's political influence and militia strength throughout the region have created a security concern for the U.S. Since the defeat of the Islamic State group, Iran-backed fighters have expanded their influence in the region. 

The presence of American forces in Syria makes it more difficult for Iran to move weapons into Lebanon, for use by its proxies, including the Lebanese Hezbollah, against Israel.

For example, the al-Tanf garrison in southeastern Syria is located on a vital road that can link Iranian-backed forces from Tehran all the way to southern Lebanon — and Israel's doorstep. So troops at the U.S. garrison can disrupt what could be an uncontested land bridge for Iran to the eastern Mediterranean.

Not the first US-Iran exchange of strikes

One of the deadliest flare-ups between the U.S. and Iran-backed groups occurred in December 2019, when U.S. military strikes in Iraq and Syria killed 25 fighters and wounded others from the Iran-backed Kataeb Hezbollah Iraqi militia. The U.S. said the strike was in retaliation for the killing of an American contractor in a rocket attack on an Iraqi military base that it blamed on the group.

In August 2022, the U.S. carried out strikes targeting Iran-backed militias in Deir el-Zour province. The Pentagon said the attacks were meant to send a message to Iran, which the U.S. blamed for a number of drone attacks, including one that targeted the al-Tanf garrison. That base was also hit in January, when three suicide drones struck, wounding two Syrian opposition fighters. The U.S. again said Iran-backed groups were responsible.

Israel has also struck Iranian targets in eastern Syria, although it rarely claims responsibility. In November 2022, airstrikes targeted tanker trucks that crossed from Iraq into eastern Syria. The convoy was reportedly carrying fuel and weapons to militias in Deir el-Zour. The U.S. denied involvement, and an Israeli military official later strongly suggested that Israel was behind the strike. 

(With AP inputs)