The trajectory of the Syrian conflict has changed considerably in recent weeks. The United States, working by, with, and through local ground forces is poised to begin the assault on Raqqa, the Islamic State’s most important urban area in Syria.
US-Turkish relations now hinge along a 50 km (31 mile) front line, snaking east to west along the Sajur river, and down to a smattering of small villages south of the town of Arimah. Various forces are now in control of intersecting front lines, including: Syrian Kurdish, Kurdish allied Arab forces, American Special Forces, Syrian regime elements, Russian Special Forces, Iranian units, Turkish military units, and Turkish allied forces. These groups—many of them hostile with one another and engaged in battle elsewhere in Syria—are now within mortar range. The events that led to the current state of affairs began years ago, but the implications of the recent moves in Syria could signal a potential settling of conflict lines, perhaps resulting in a de-facto outcome for iterative talks between the various warring parties, first to de-escalate along front lines, and then for a broader peace arrangement.
Manbij: A Failed US-Turkish Effort
In November 2014, former Vice President Joe Biden reached a tentative agreement with then Turkish Prime Minister Ahmet Davutoglu to cooperate in Syria. For much of that year, the United States and Turkey were locked in negotiations about Incirlik Air Force Base in Adana, Turkey for strike missions and an airbase in Diyarbakir for Combat Search and Rescue (CSAR). The two sides remained at odds over how best to pursue shared goals: using military force to defeat the Islamic State (ISIS, ISIL, or Daesh), while simultaneously providing arms and training to elements of the Arab dominated opposition to force Bashar al-Assad to make political concessions.
For Turkey, Incirlik was a key source of leverage with the United States. The base is 113 km (70 miles) from the Syrian border, which would allow coalition pilots to remain on station for longer and to ease the burden placed on US tanker assets that assist pilots flying from airbases in the Persian Gulf. Turkey, as a condition for opening the base, demanded that the United States establish a no-fly-zone over northern Syria, extending as far as Aleppo. For the United States, the threat of ISIS superseded that posed by the regime. The negotiations were inconclusive.
Meanwhile, east of the Euphrates, American airpower (flying from outside of Turkey) continued to give support to the Syrian Kurdish People’s Protection Units (YPG), a militia linked to the Kurdistan Workers’ Party (PKK). The PKK has waged an insurgency inside of Turkey for more than three decades, first for Kurdish independence, and then for political autonomy. The YPG’s advance, in turn, prompted Turkey to re-evaluate its demands with the United States, in favor of joint action west of the Euphrates. Ankara sought to limit Kurdish expansions west of the river to block the YPG from consolidating control over a strip of territory along Turkey’s longest land border.
In late July 2015, the Turkish government opened Incirlik to coalition aircraft to armed intelligence, surveillance, reconnaissance (ISR) missions. The first strike from an armed MQ-1B took place in early August, outside of Tel Abyad, and in support of advancing YPG. Shortly thereafter, American aircraft began strike missions. The Turkish government, in turn, began discussions to clear the Manbij pocket with Arab and Turkmen forces, based in towns stretching from Azaz to Marea. These negotiations resulted in three interrelated agreements: 1) The United States, with Turkish support, would expand its training program to include the rebels then based in northern Aleppo; 2) Turkish aircraft would patrol this area, which, along with artillery moved to the border, would support this group’s operations against ISIS; 3) The US would deploy Special Operations Forces to Kurdish held territory and began the training of Arab forces, dubbed the Syrian Arab Coalition (SAC).
The Pentagon, however, lacked the legal authority to operate in these areas, prompting the passage of H.R. 3979, which included the Title 1209 authorities governing American military support to the Syrian opposition. The authorities bar the United States from directly arming the YPG (without a Presidential waiver), but allow for the provision of weapons to the SAC—which fights with the YPG as part of the Syrian Democratic Forces (SDF).
The Train and Equip (T&E) program was intended to close the Manbij pocket without violating Turkey’s stated redline: No YPG presence west of the Euphrates. For Ankara, the YPG’s presence east of the river was, without question, viewed with suspicion, but was less threatening than a contiguous Kurdish presence along the border. The T&E program was intended to train smaller units to help guide US air strikes, a seemingly minor task, but important for how the United States conducts air operations by, with, and through local actors, within circumscribed rules of engagement. The media coverage focused on two incidents: when Syria’s al-Qaeda affiliate, then known as the Nusra Front, attacked T&E forces near Azaz, and how one US-trained leader handed his weapons over to Nusra to buy protection. These incidents, while regretful, undermined political support for the program, leaving no viable alternative to close the Manbij pocket (other than the SDF).
The Turkish downing of a Russian Su-24, and subsequent Russian bombing in support of the YPG north of Aleppo city in February 2016, nearly wiped out the rebels fighting along the Marea line—upending the T&E program. In response, the program was scaled back. However, its successes should not be overlooked: Two T&E groups, Liwa al-Muatism and the Hamza Brigade, are now fighting as part of Euphrates Shield, alongside a smattering of other groups that continue to receive US support. However, the program failed to achieve its objective: to close the Manbij pocket without SDF forces, despite significant US support to the rebel groups, including 50 percent of strikes and ISR sorties from Incirlik. The failing prompted the use of the SDF west of the Euphrates, an operation that had initial Turkish acceptance, despite the YPG presence within the SDF. The initial push to the city began in April 2016 and ended on August 12, after a month long siege.
Twelve days later, on August 24, 2016 Turkish armor and Special Forces, trailed by various rebel groups, moved across the border into Jarablus. The timing of the operation does not appear to have been coincidental—it coincided with Vice President Biden’s visit to Ankara to express support for Turkey, following the failed July coup attempt. Days later, Turkish forces moved into al-Rai, starting a march to ISIS-held al-Bab. In the opening days of operation Euphrates Shield, the United States and Turkey reached an agreement, whereby US forces would deploy 20 km (12.5 miles) into Syria to support the offensive. At the start of operation Euphrates Shield, Turkish forces clashed with the SDF south of Jarablus, before the United States helped to broker a ceasefire to help quell clashes along SDF territory west of Manbij and along the Sajur River. The Turkish invasion, it appears, was in response to the consolidation of the SDF presence in Manbij and the likelihood that the group would soon push out, through al-Bab, to link up the YPG held Efrin canton in northwest Syria. This operation would have resulted in SDF control over the Turkish border, an untenable outcome for Turkish security officials.
Read more from the source article published by the Atlantic Council Mar. 9 2017