Syria’s six-year civil war just escalated to a new level.

Less than 24 hours after a U.S. F/A-18E Super Hornet shot down a Syrian Air Force Sukhoi SU-22 fighter-bomber outside the southern city of Tabqa, the Russian government stated that it would treat all coalition aircraft operating west of the Euphrates River “targets.”

“The destruction of the Syrian Air Force [jet] by American aircraft in Syrian airspace is a cynical violation of the sovereignty of the Syrian Arab Republic,” the Russian Defense Ministry said in a statement on June 19, assailing Operation Inherent Resolve as a front for Western geopolitical domination. “The repeated fighting of the United States of America under the cover of ‘counter-terrorism” against the legitimate armed forces of a member state is a flagrant violation of international law and in fact military aggression against the Syrian Arab Republic.”

Citing the U.S.-led coalition’s failure to contact Russian command through “existing channels of communication,” the Ministry of Defense bailed on the incident-prevention hotline outright and eliminated coordination between coalition commanders over operations surrounding the “de-confliction zones” that have been flashpoints for escalating skirmishes between coalition and pro-regime forces.

“In the areas of Russian aviation in the sky, all air facilities, including aircraft and unmanned vehicles of the international coalition found west of the Euphrates will be escorted by Russian air and air defense aircraft,” the Ministry of Defense stated.

The downing of the SU-22 marks the U.S. military’s first air-to-air kill since 1999, when Serbian Mig-29 was shot down as part of NATO’s Operation Allied Force. Coalition aircraft “will continue to conduct air operations throughout Syria,” OIR spokesman Col. Ryan Dillon told Foreign Policy on June 19, adding that the shootdown was “accordance with the rules of engagement and international law.”


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“The Coalition is always available to de-conflict with the Russians to ensure the safety of Coalition aircrews and operations,” a OIR spokesman told Task & Purpose via email. “The de-confliction line has proven effective at mitigating strategic miscalculations and de-escalating tense situations.”

The Russian military has provided air support in Syria for forces loyal to longtime ally President Bashar al-Assad since 2015. The Russian broadsides come as the U.S.-led coalition finds itself facing an increasingly crowded operational area in its fight against ISIS. The downing of the Syrian SU-22 marked the culmination of more than a month of incursions by local militias aligned with the Assad regime into a de-confliction zone at the At Tanf garrison on the Syria-Iraq border, forcing coalition forces to call in defensive airstrikes against pro-regime convoys and artillery.

On June 8, a U.S. F-15E Strike Eagle shot down an Iranian-made drone that deployed munitions near coalition forces, prompting the Pentagon to relocate an M142 High Mobility Artillery Rocket System from Jordan to the At Tanf in response.

“This blatant aggression confirms beyond doubt the truth … the American position aims to try to influence the Syrian Arab Army’s ability [to] exercise its legitimate right to fight terrorism,” the Syrian government said in a statement following the SU-22 shootdown, echoing the Russian Defense Ministry’s language. “This attack comes at a time when the Syrian Arab army and its allies are advancing in the fight against ISIS terrorists who are being defeated in the Syrian desert in more ways than one.”

In response to the string of incidents with and Russian forces, coalition forces have “taken prudent measures” to “reposition aircraft over Syria so as to continue targeting ISIS forces while ensuring the safety of our aircrew given known threats in the battlespace,” an OIR spokesman told Task & Purpose.

While the escalating clashes between coalition and pro-regime forces may end up drawing the United States into an outright conflict with the Syrian military, Russia isn’t the only player backing the Assad government. Hours before the shootdown, the Iranian Revolutionary Guard announced that it had targeted ISIS fighters with Zolfaghar ballistic missiles in the eastern Deir Ezzor region of the country. CNN reports that the strikes, launched in response to the twin terror attacks that left at least 16 dead capital at the Iranian parliament and a beloved shrine in Tehran on June 7, mark the first time the Iranian regime has fired missiles at another country since the Iran-Iraq war three decades ago.

That the Russian government explicitly cited the de-confliction zones that are proving fertile ground for clashes between the various armed forces operating in war-torn country suggests that tensions will only widen beyond the “self-defense” proxy war that comes with supporting Syria’s warring factions against their mutual enemy of ISIS. And with Russia and Iran deepening their military involvements in the region while cutting off avenues of de-escalation with coalition commanders, it’s almost certain that the Pentagon’s first air-to-air killed in almost 20 years won’t be its last.