The recent flare-ups have come suddenly, but the conditions for them were being set soon after protests against the Assad regime in Syria erupted into a full-blown civil war some seven years ago. The conflict quickly sucked in other countries. Iran entered the conflict in 2011 to help prop up Assad’s regime as it faced growing nationwide protests. Hezbollah
, the Lebanese militia that acts as an Iranian proxy, joined in soon afterward, at a point when the regime looked in danger of falling, helping Assad hold off the rebels—some of whom received covert American support. The United States started bombing ISIS and al-Qaeda positions in Syria in 2014. Then in 2015, when Assad’s grip on power appeared to be in peril again, Russian President Vladimir Putin intervened on his behalf.
“Putin’s number one operational goal in Syria is to stabilize and prop up the Assad regime, including the return of previously rebel or ISIS held territory under regime control,” Alina Polyakova, a fellow at the Brookings Institution’s Foreign Policy Program, said in an email. “Putin’s strategic goal has been to establish Russia as the key power broker in the Middle East.”
During this same period, while Americans were supporting various rebel groups, the Kurds emerged among the most capable fighting forces in the conflict
, but remained a source of mortal fear for Turkey, which had fought a decades-long Kurdish insurgency on its own side of the Syrian border. Turkey viewed the Kurds allied with the U.S. as terrorists
, even while it also opposed the Assad regime. Hence Turkey supported other rebel groups, including Islamist ones, fighting the Syrian president.
Source : https://www.theatlantic.com/international/archive/2018/02/syria-conflict/553154/