Syria is the playground where the world powers are fighting each other without actually fighting each other. On one side, you used to have America, the EU, Turkey & the Kurds. On the other side, you had Syria, Russia, & Iran. American troops in the border area were sorta keeping the lid on things. Erdogan (Turkey) phoned Trump 3 days ago (?) and after the phone call, Trump surprised everyone (incl his Generals) by saying American troops were pulling out.
This allows Turkey to commit genocide against the Kurds (who were American allies until that phone call). It also increases Russia's influence in the Middle East while nobody will trust America again. It seems that every decision Trump makes benefits Putin & Russia.
I'd say there'll be another (proper) war in the area in the next few months, just in time for the American 2020 elections...