Go live in the Third World for awhile to open your eyes. It's not the same as here. It's not the same as what you see in sanitized videos.
In the Middle East, the people there are very tribal. To help keep everyone under control and somewhat peaceful, the ones in power have terrorized and killed dissenters. They have done this by funding and supporting groups of thugs which we call terrorists. These goons have been used to have proxy wars with their neighbors and on their own citizens.
Assad's father and grandfather were ruthless dictators on Syrian. He is too. I know this doesn't fit the image inside your head right now.
The other ME leaders have recognized this previously practice has gotten way out of control. They've banded together trying to wipe out their ugly creations. Assad has not and continues to support terrorists.