His alternatives are dealing with Russia and Iran. He's not going to want to do that because he was fighting them.
So it makes sense for him to put on a suit and make a deal with the Americans.
He’ll make a deal with the US, and once he gets the money and arms he needs, he’ll be back to pushing the Al Quaeda agenda. Trump lifting sanctions on Syria under Al-Sharaa was a bad case of hugging a tar baby. Let the Gulf oil states bankroll and arm him if they want, as long as he doesn’t start causing problems for us.