The letter, signed by nearly 400 lawmakers from across the Senate and the House of Representatives, urges Trump to send “a message of resolve to malign actors in the region” – including Iran and Russia.
The Islamic State group (ISIS) lost control of its last holdout in Syria’s Baghouz, Deir ez-Zor province in March this year. However, its remnants and sleeper cells are still thought to pose a threat.
There are also concerns about Al-Qaeda’s former Syrian affiliate, Hayat Tahrir al-Sham (HTS), which controls the northwest province of Idlib.
Damascus has launched a fresh offensive with Russian air support to dislodge the jihadist group, leading to the worst bloodshed seen in months.
Although the latest offensive is localized to Syria’s northwest, the bipartisan letter warns the escalation in Idlib could further “destabilize the region” and threaten US allies.
“As some of our closest allies in the region are being threatened, American leadership and support are as crucial as ever,” the letter states.
Trump has been reluctant to maintain the US troop presence in northern Syria, where roughly 2,000 personnel were stationed in support of the Kurdish-led Syrian Democratic Forces (SDF) in the fight against ISIS.
In December 2018 he announced the full and imminent withdrawal of all US personnel, disregarding the advice of his own national security team and allies. He backpedaled in February, allowing for a fraction of troops to remain.
Trump’s call for a fall withdrawal caused outcry and prompted the resignation of US Defense Secretary Jim Mathis and the special envoy to the anti-ISIS mission Brett McGurk.
Signatories also called on Trump to “increase pressure on Iran and Russia with respect to activities in Syria,” accusing both countries of attempting to change the trajectory of the war “at the expense of Syria’s people.”
Moscow intervened in the Syrian Civil War in 2015. Russian airpower and military advisors helped turn the war in the regime’s favor, eliminating rebel holdouts in the country’s south and suburbs of the capital in 2018.
However, US lawmakers voiced particular concern about Iran’s “destabilizing” influence, highlighting its use of proxies in support of Syrian President Bashar al-Assad and use of Syrian territory to launch drones and fire missiles into Israel.
Escalating tensions in the Persian Gulf have diverted attention away from the US role in Syria.
In recent days, the US has withdrawn non-emergency personnel from its Baghdad and Erbil missions and urged US citizens to leave the country, citing an unspecified threat from Iran and its proxies. The US has also deployed an aircraft carrier group and B52 bombers to the Gulf.
Trump hopes the move will bring Iran to the negotiating table, but observers fear such brinkmanship threatens plunging the region into war.
