Syrian Kurds united by the the Democratic Union Party (PYD) are a major faction fighting the militants in Syria. Indeed, they are the second most important anti-terrorist military power in the country. Since the war’s start, the relations between PYD and the Syrian government have been based on the fact that the government wasn’t able to oppose both Islamist militants and Kurdish autonomy movement at the same time.
This is the source of the Damascus’ “social pact” with Syrian Kurds. They have obtained a kind of autonomy governed mainly by the PYD. At the same time, they have become an alternative to the Syrian Arab Army as an anti-Islamist force. It should be noted that the Kurdish military capability is less than ISIS’ or al Nusra’s, and PYD’s forces have used the Syrian government assistance, mainly the air support and arms supplies, in order to oppose Islamist militants. Their weakness is also the reason why Kurds have allowed al-Nusra’s armament supplies through the Turkish border for a long period of time. They tried to avoid a direct confrontation against pro-Saudi militants.
It’s clear that the Syrian Kurds aren’t able to conduct full-scale offensive operations if the Syrian government forces and the Russian Air Force don’t do it at the same time. US support might help in that regard. However, any PYD offensive efforts will require not only material and technical support, but also significant air support. So the US would need to send military advisers to coordinate PYD’s units and US air support. This could lead to battle casualties among American servicemen and will likely lead to tensions in relations with Turkey.
The PYD aims to create an “Independent Kurdistan”, or at least an autonomy. Which means they cannot be a staunch ally genuinely interested in resolving Syria’s domestic problems. Syrian Kurds will pursue their goals using ad-hoc alliances with any side if it helps them in their quest to establish their own state. This showcases another important feature of the Kurdish factor in Syria.
PYD’s offensive actions are geographically limited to the territory inhabited by Kurdish populations. In the best case, the Kurdish advance will be ended in the suburbs of Raqqa.
Thus the Kurdish autonomy could become a buffer zone in Syria stabilizing the situation in Syria by interdicting the Islamist militants’ supplies. But it is hard to believe that Syrian Kurds could become a power aimed on solving the crisis in non-Kurdish areas of the region.