There you go! Straight from the Donkey(of a different colour)’s mouth.
The Kurds of the SDF are, as I have always said, paid US mercenaries or de facto US ground troops (because they could not round up sufficient conditioned troops of their own to do the job).
The SDF simply replaced IS militants (also one time US allies) who were found to be not up to the task and were taken out of the game (which is polite talk for ‘having the shit bombed out of them’), some of the remainder of which now sit festering in SDF prison camps awaiting their fate. The SDF, now having become a redundant and troublesome burden for the US, are to be similarly thrown to the wolves.
There is a lesson to be learned in there somewhere, for current or hopeful US allies.