Utilising the chaos in Syria in the wake of Bashar al-Assad’s ouster, Turkey has mobilised its military along with militias it sponsors along the border with Kurdish-held Syrian territories in what appears to be a preparation for an imminent invasion, according to a report
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Biden hasn’t proved to be an ally either. He might not support Turkey but he isn’t going to allow US troops to return fire. It will be like the UN Outposts Israel just goes around.
As far as I know, procedures for returning fire don’t require calling the president. There already was an incident about a week ago - they just shot down the drone that threatened them.
Basic stuff like that they can do. But stray artillery rounds aren’t going to get a response. Anything more than their rifle or short range anti air requires permission from higher up. And even those are on a short leash because the local commander will be under orders to hold fire unless they’re actually attacked.
On the other side there will be an American officer telling the Turks exactly where American troops are and acting as the first line of deconfliction if there are any mistakes. Turkey will listen to that officer because of the balance of power in the US-Turkey relationship and the knowledge that the US is capable of disabling their entire military overnight.