How Turkey's push into Syria is shaking the Middle East's web of alliances

As civil war continues to rage in Syria and the Islamic State movement clings to control of territory it captured in 2014, long-time alliances and rivalries are shifting in the Middle East. Wednesday's incursion into northern Syria by Turkish tanks and infantry, backed by U.S. air support, is a case in point. Patrick Martin provides a guide to the forces at work

Where Turkey's interests lie

With Islamic State

Turkey is a member of the U.S.-led coalition against the Islamic State but, until now, its overt actions against the radical movement have been limited. Indeed, when IS fighters in 2014-15 threatened the Kurdish city of Kobani in Syria, Turkey declined to join the fight against IS forces and even shelled Kurdish positions instead. As well, IS recruits and weapons often crossed into Syria through the Turkish frontier, a situation often criticized by Washington.

With Syria

The once-friendly relations between Turkey and Syria have been dashed as a result of Syria's civil war. Ankara strongly opposed the violent response by the regime of Bashar al-Assad to popular protests – anticipating the spillover effects a civil conflict would cause. Turks resent the flood of Syrian refugees they must care for, the growth of Kurdish militancy that benefited from the Syrian chaos and the spread of Shia power from Iran and Hezbollah into a widely Sunni region. For the moment, Turkey likely hopes that its incursion into Syria will stop Kurdish ambitions in northern Syria without necessarily benefiting the Assad regime.

With the Kurds

Ankara views the militant Kurdistan Workers' Party (PKK) in Turkey as one of the country's greatest threats, and views the YPG (the military wing of Syria's Kurdish movement) as the offspring of the PKK – condemning both as terrorist groups bent on establishing a Kurdish state. The YPG has taken advantage of the chaos in Syria to capture many of the communities along the border with Turkey, pushing west across the Euphrates to link up with a Kurdish enclave north of Aleppo – a move Turkey is determined to prevent. The YPG has condemned Wednesday's Turkish incursion as "blatant aggression in Syrian internal affairs."

With Russia

Historic enmity between the two countries surfaced in November, 2015, when Turkey shot down a Russian fighter jet that had been attacking Turkmen Syrian rebels near the Syrian-Turkish border. Russia is helping defend the Assad regime, much to Ankara's disapproval, at least until recently. Turkish President Recep Tayyip Erdogan has sought to restore friendly relations with Moscow – sending a letter of apology to Russian President Vladimir Putin for the downing of the warplane, and visiting Russia earlier this month. It is likely that Ankara also will re-evaluate its attitude toward the Russian-backed Syrian regime.

With the U.S.

Long-standing allies in NATO, Turkey allowed the U.S.-led coalition against the Islamic State the use of Turkish airfields. But Mr. Erdogan was disappointed the United States did little to remove the Assad regime in Damascus, and that it supported the Kurdish YPG in Syria. However, U.S. support for Turkey's incursion into Syria on Wednesday changes things. Washington continues to view the YPG as an ally against IS, but agrees with Ankara that YPG forces must remain east of the Euphrates. Turkey and the United States continue to disagree about the possible extradition of a Turkish religious figure alleged to be the mastermind behind an attempted coup in July.

Where the Kurds' interests lie

With Syria

For years, the Assad regime left Syrian Kurds pretty much alone and Kurds did little to push for their own state. They stayed out of Syria's civil war for the first three years and the regime let the Kurdish political movement (PYD) take control of Kurdish villages along the Turkish border. When Islamic State fighters threatened their communities in 2014, the YPG fought back and the militants partnered with other U.S.-backed groups to drive IS forces out of the area, giving control increasingly to the Kurds. Earlier this month, regime forces attacked the YPG for the first time, signalling that the Kurds had gone far enough.

With Islamic State

The Kurds in both Iraq and Syria have been among the most effective in combatting Islamic State fighters. In Iraq, they have won back all the territory they lost in 2014 and are closing in on Mosul. In Syria, they successfully defended their main communities, such as Kobani, and now, having partnered with other U.S.-backed forces, they have pushed IS fighters out of areas west of the Euphrates, such as Manbij, which they took in heavy fighting this summer.

With the U.S.

Washington has come to view the Syrian Kurds of the YPG as the best fighters in the U.S.-backed Syrian Democratic Forces (SDF) that are battling the Islamic State. With U.S. support, the SDF pushed IS fighters back from Manbij, west of the Euphrates. The victory, however, upset Turkey, which fears Kurds will come to control the border area with Turkey. This triggered Turkey's incursion into Syria Wednesday and led U.S. Vice-President Joe Biden to tell the Kurds they must return to the other side of the Euphrates River, a move that incensed the YPG.

Where Syria's interests lie

With Islamic State

The Islamic State, a radical Sunni movement, views Alawites such as the Assads as apostates and seeks to overturn their hold on power and to build an Islamic caliphate. Backed by money from the Gulf and armed with recruits and weapons from all over the world, the group succeeded quickly in capturing 35 per cent of Syrian territory, mostly in the east and north of the country. Regime forces, focusing on other rebel fighters, have largely left the fight against IS forces to the U.S.-led coalition and the Kurds, until now.

With Russia

The Syrian regime was exhausted and vulnerable in the fall of 2015, when Russia came to the rescue. Its deployment of heavy bombers and agile helicopter gunships provided a respite to pro-regime troops. Russia views Damascus as an long-time ally and a client worth saving, and sees its best opportunity for influence in the region in backing the Syria-Iran-Hezbollah side of the regional divide. Like the United States, the Putin administration also views the Islamic State with horror and wants the group to meet its end in Syria.

Where America's interests lie

With Islamic State

Washington considers the eradication of the Islamic State to be the No. 1 job in Syria and Iraq and assembled a coalition of 40 countries to wage an air war against IS fighters. The coalition provides air support to local militias battling IS forces and Washington has deployed U.S. Special Forces to train fighters on the ground in Syria. The United States' aversion to IS has brought it into a subtle partnership with Iranian-backed militias in Iraq and with Russia, an important defender of the Assad regime, in Syria.

With Russia

Ostensibly backing opposing sides in Syria's civil war – Russia is helping defend the Assad regime and the United States backs rebel groups opposing the regime – the two countries find common ground in their opposition to the Islamic State. They have drafted an agreement on how to proceed jointly against IS forces, though some in Washington view it as too helpful to Damascus. Russia expressed concern Wednesday about the U.S.-backed Turkish incursion into northern Syria.

With Syria

While the Obama administration was quick to condemn the Assad regime at the outset of the Syrian civil war and to call for the Syrian leader's resignation, Washington has done little to make that happen. Wary of putting boots on the ground, or of backing the wrong kind of rebel forces, the United States has primarily limited its efforts to combatting Islamic State fighters from the air and to working with Russia in vain attempts to find a political solution.

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