Nobody in Syria likes us very much. There are factions upon factions upon factions who hate each other with the fire of a thousand burning suns, and they only reason they're not trying to kill us is because they're too busy trying to kill each other. And when we interrupt them from killing each other, they'll all turn around and try to kill us.
We have just interrupted our enemy in the middle of them making huge mistake after huge mistake. What the fuck, Trump? What the fuck, McMaster? What the fuck, JCS? Were you people so itching for a fight you had to jump into the middle of the biggest shit show in the Middle East? When did "The Art of War" go out of style? Do people not read it anymore?
There is no victory in Syria. There is no "winning". We can't "win so big" with Assad, because beating Assad means that Terrorist Group A comes to power, assuming that Terrorist Group B doesn't kill them off first and take the throne. There is not a single group of people in Syria who are our pals. Any of them in control of the country is a bad idea. Helping one over the other will only mean that one group hates us slightly less, but they'll still send terrorists over to blow up Americans when they can. And the other groups will probably swear blood feud because we didn't give their terrorists priority over Terrorist Group A's terrorists.
You want to help Syria? You build refugee camps outside of the country and make sure that the insanity of Syria stays in Syria. Other than that, you build a wall around the country, seal it up and wait for the various terrorists, dictator-wanna-be assholes and the actual dictator to kill each other. And when there's only one or two people left you tell them "If any of this shit show makes it to our shores, we will bomb your country until it's nothing but rubble from one side to the other. And then we'll bomb it to make the rubble bounce."