I thought the 900 US troops were there since the former Trump administration, and remember when Trump had the Iran military guy killed, many thought that was a good thing. I don’t think Biden made any increases from the number Trump left there. These 900 were specifically to block ISIS, and to help the Kurds who gave us lot of support in northern Iraq in earlier wrs. Unfortunately, there are Kurds in conflict in Turkey with the Erdogon government which is a complication there.
You remember correctly. The US troops in Syria were there to defend, well, everyone, against ISIS. And to keep the Turks from messing with the Kurds.