Obama was ready to attack Syria and only refrained from doing so when they, and the Russians, guaranteed they were turning over their
chemical weapons for neutralization. He kept his word, they broke theirs.

They did not use real chemical weapons (stuff like Chlorine is just the use of an industrial gas, toxic, but not in the way stuff like nerve agents like Sarin are. They clearly held back on using NBC weapons until Obama was gone, who had the implied legal right to retaliate, in order to test Trump. It is clear the Syrian regime didn't need to do this, they are winning the war, they did it just to demoralize their opposition and humiliate their international opponents..

Trump inherited that right, and he exercised it legally, and in my opinion, effectively and with restraint. I am still fundamentally opposed to the Trumpster in every way, but in this, I support him.