Aron Lund writes: The Syrian Democratic Forces, or SDF, is a coalition of Kurdish, Sunni Arab and Syriac Christian fighters, but is completely dominated by its Kurdish element, which is a powerful and well organized militia known as the Popular Defense Units, YPG, with an all-female branch called the Women’s Defense Units, or YPJ. These organizations, in turn, are Syrian front groups for the Kurdistan Workers’ Party or PKK. The other militias involved in the Syrian Democratic Forces are either long-standing PKK allies or proxies, such as the armed wing of the Syriac Union Party, or more recent allies drawn from the Sunni Arab tribal landscape in this part of Syria and from the remains of small Sunni Arab rebel groups crushed by the so-called Islamic State.

The coalition as a whole receives American air support for operations against Islamic State, as did the YPG/J before it. That started in the Battle of Kobane that began in autumn 2014, which was enormously successful — really the first major battlefield defeat inflicted on Islamic State. It has provided the template for US-PKK cooperation. In addition, the Pentagon has picked out a number of these little Arab groups that work under the SDF umbrella as favored recipients of arms and support. It terms them, collectively, the Syrian Arab Coalition, though no one else seems to use that name.

The idea is to use the SDF as an incubator to breed Sunni Arab militias able to take over where Kurdish territory ends and push deep into Islamic State’s heartland, which is in the Sunni Arab tribal region that connects Syria with Iraq. Relying on the Kurds in that region would create resentment among other Syrian and regional allies, and it would risk pushing locals into the arms of the jihadis. Also, it’s not obvious that the Kurds are interested in dying for U.S. interests that far away from their own home areas. They have many other priorities, chief among them to try to secure their population, to keep Turkey out of Syria and to link the Kurdish enclaves in Kobane and Efrin, which are separated by territory held by Islamic State and rival Turkey-backed Sunni Arab rebels north of Aleppo. In those battles in northwestern Syria, the SDF fighters seem to have received some level of Russian support, but they do not enjoy any U.S. backing – though they like to pretend they do, in order to sell their war on Turkey’s allies as part of the “War on Terror.” Of course, this has embarrassed the Pentagon in front of other American allies, but what can be done? All sides in Syria, including the United States, must balance between allies that do not fully share their own interests. [Continue reading…]