Yesterday a fight broke out between Syrian Arab Army troops and local Kurdish forces in the predominately Kurdish city of Hasakah in north-eastern Syria. Hasakah, with some 200,000 inhabitants, has held a SAA garrison for years. There is some enmity between the Kurds and the soldiers but the situation is generally peaceful.
There have been earlier fights but these were local rivalries between Syrian auxiliary National Defense Forces from local Arab (Christian) minorities and some gangs who form a Kurdish internal security force under the label Asayish. Such fights usually ended after a day or two when grown-ups on both sides resolved the conflict over this or that checkpoint or access route.
The Islamic State (grey on the map) once threatened Hasakah but that danger is now far away.

Map via ISW
Yesterday another fight broke out, but got serious. The Syrian air force was called in to defend against direct attacks on the SAA garrison and minority quarters:
Syrian government warplanes bombed Kurdish-held areas of the northeastern city of Hasaka on Thursday for the first time in the five-year-old civil war, the Syrian Kurdish YPG militia and a monitoring group said.
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The Syrian government still has footholds in the cities of Qamishli and Hasaka, both in Hasaka governorate, co-existing largely peacefully with YPG-held swathes of territory.The cause of this week's flare-up was unclear.
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Xelil said government forces were bombarding Kurdish districts of Hasaka with artillery, and there were fierce clashes in the city.The Syrian Observatory for Human Rights, which tracks the war using a network of activists, said warplanes had targeted Kurdish security forces' positions in the northwest and northeast of the Hasaka city.
The reason that fighting started might have to do with U.S. troops who, for whatever reason, seem to be in Hasakah. The U.S. military now laments that these troops came under Syrian air force fire:
The Syrian airstrikes took place in the northeastern city of Hasaka, an area that has seen increasing ground clashes between the Kurdish YPG fighters present and the Syrian regime forces. There was a small number of U.S. Special Operators acting as advisers to the YPG when the Syrian airstrikes began.
After the Syrian Su-24s began to strike, the U.S. immediately contacted the Russians, Davis said, and made clear that American aircraft would respond if coalition forces were under attack.
The Russians explained that they were not the ones conducting the strikes and the U.S. scrambled manned fighter aircraft to the area to protect the Americans and allies under attack.
By the time the U.S. and coalition aircraft arrived the Syrian attack jets had left.
There is no Islamic State in the area which is now far away from the front line.
- Why are U.S. troops, who have zero legal grounds of being in Syria at all, in Hasakah city or the wider area?
- Who are they "advising" there and for what purpose?
- Why does rare local fighting starts to get serious just when U.S. troops are in the area?
The U.S. has the chutzpah to "warn" the Syrians of defending their own troops on Syrian grounds:
Additional U.S. combat air patrols have been sent to the area yesterday and have been flying there today, as well.
Davis said that the Syrians would be "well-advised" not to interfere with coalition forces on the ground in the future.
Syrian government forces are attacked by Kurdish troops who are "advised" by U.S. special forces. According to the U.S. spokesperson the Syrian air force is not allowed to defend them? What has this to do with "fighting ISIS" in eastern Syria which is allegedly the sole reason for U.S. troops being in Syria?
The Syrian air force was back over Hasakah today and continued to bomb position from which the Syrian army was attacked. They would not be flying there without Russian consent. Does the U.S. military want to start a fight with the Syrian air force and its Russian backers?
The YPG Kurds claim they are now evacuating civilians from some city quarters. They seem to expect a prolonged conflict.
Any move against the Syrian army in Hasakah will be watched carefully from Ankara. Turkey fears, with valid reason, that the U.S. supports the Kurdish aim of a national entity in Syria and Iraq. This would endanger Turkey with its own large Kurdish minority.
If the Kurds expel the Syrian forces from Hasakah with U.S. support, Turkey would know that any U.S. claim to not work against its Turkish ally interest is false. This would deepen already high Turkish animosity against the U.S. and would accelerate its move towards some alliance with Russia and Iran.