Turkish tanks and troops backed by U.S. air support flying out of Incirlik Air Base crossed into Syria on Wednesday with the intent of taking the border town of Jarablus -- partly to stop it from falling to U.S.-backed Kurdish militias.
President Recep Tayyip Erdogan said that the cross-border action, called Operation Euphrates Shield, was in response to recent terror attacks claimed by ISIS in Turkey but was also aimed at the Syrian Kurdish PYD, or Democratic Union Party. The military wing of the PYD is the YPG, or People's Protection Units, which has been the most effective U.S.-backed opposition force in northeastern Syria.
In a speech to the Turkish parliament, Erdogan said the move against Jarablus targeted "terror organizations such as Daesh [an Arabic acronym for ISIS) and the PYD," Turkey's Hurriyet newspaper reported. "They challenged us. They said, 'This and that will happen to Turkey in Syria.' Now I am addressing them: You should think of what will happen to yourselves."
The cross-border action began with a barrage at 4 a.m. Wednesday from Turkish TSK 155mm self-propelled howitzers and rocket launchers, Turkey's Anadalou news agency reported. The barrage was followed by at least 12 airstrikes.
More than 20 tanks joined by other tracked vehicles reportedly crossed the border in support of contingents of the Free Syrian Army, another opposition group backed by the U.S. By midday Wednesday, the attacking force reportedly had advanced to the Jarablus town center.
A senior Obama administration official traveling with Vice President Joe Biden, who was on a fence-mending, one-day visit to Ankara, said the U.S. had agreed to provide close-air support for the action against Jarablus.
In a visit to the Turkish parliament, which was bombed during a failed military coup on July 15, Biden warned the YPG that they would lose U.S. backing if they failed to meet the demand of NATO ally Turkey to stay west of the Euphrates River and away from Jarablus.
"We have made it absolutely clear that they must go back across the river," Biden said. "They cannot, will not and under no circumstances get American support if they do not keep that commitment. Period."
Syria's Foreign Ministry condemned the Turkish incursion as a "blatant breach to its sovereignty," Syria's state news agency reported. "Fighting terrorism on Syrian territory from any side should have been coordinated with Syrian government," the Foreign Ministry said.
Turkey has repeatedly complained about U.S. support for the YPG. In May, Turkish officials were incensed when U.S. Special Forces troops training and advising the YPG in northeastern Syria showed up in Agence France Presse photos wearing YPG arm patches.
Army Lt. Gen. Sean MacFarland, then-commander of Combined Joint Task Force-Operation Inherent Resolve, immediately ordered the troops to take off the patches.
"Wearing those patches was unauthorized and inappropriate, and corrective action has been taken. We have communicated as much" to Turkey, said Army Col. Steve Warren, MacFarland's spokesman at the time.
Turkey regards the PYD, and by association the YPG, as terrorist organizations linked to the PKK, or Kurdistan Workers Party. The State Department has designated the PKK as a terrorist organization.
Biden's visit was meant to allay widespread suspicions in Turkey that the U.S. may have been involved in the failed coup attempt, and also to gauge how Erdogan's recent overtures to Russia would affect U.S.-Turkey relations.
Erdogan has charged that Fethullah Gulen, an Islamic cleric now living in Pennsylvania, was behind the coup attempt and demanded his extradition.
"Our legal experts are working right now with their Turkish counterparts on the production of an evaluation of material and evidence that needs to be supplied to an American court to meet the requirements under our law in the extradition treaty to extradite Gulen," Biden said during a news conference with Prime Minister Binali Yildirim.
Earlier this week, Yildirim raised concerns with the U.S. and NATO allies by raising the possibility that Russia might be able to share the air base at Incirlik with the U.S.
-- Richard Sisk can be reached at Richard.Sisk@Military.com.