The US power structure wants to insulate EU from China and Russia's growing influence in the Eurasian region.
The way to accomplish this is to make sure both Syria and Turkey remain with the US and EU - something which is falling apart with Erdogan and Russia's presence in Syria. Look at a map, Syria/Turkey are the final puzzle pieces, or territories in the board game Risk.
As a result of this shift, the US will look to cut off the Chinese OBOR strategy (via Turkey/Greece) and also stifle Russia's oil pipeline plans (via Syria). This is what the entire conflict in the Middle East has been about, and will continue to be about moving forward. (1) Economic influence and (2) oil.
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