"The Genocide Convention, which the U.S. and Syria have ratified, requires state parties to act towards “preventing and punishing genocide.”
Syria's Civil War Has Become a Genocide
It was the reason given for fighting against ISIS (because of the threat of genocide against the Yazidis...and Christians, if I remember correctly).
By the dictator who is only there because of "99%" votes in favor of him (with supposedly a 99% voter turn-out) after his dictator father came into power through the military coup and also quashed a rebellion by killing thousands? I mean, no one in their right mind believes he actually won those "elections".
The majority (most Sunnis) do not want him. And that is who Russia is also helping to kill off.
It's obvious Iran (which does not border Syria) supports the Alawite Shi'as and doesn't want the Sunni majority to take back their country from their oppressors. The rebels didn't do anything to the Iranians until Iran started sending IRG to prop Assad up to prevent his fall (and also has been sending Afghan and Pakistani Shi'a fighters to Syria to fight too)....and even that is within Syria, not inside Iran.
Not against ISIS; my own posts confirm that (they are actually strengthening ISIS).
Actually the main point is that the world stands silently as there is a very real genocide going on and civilians are bearing the brunt of the violence which you defend (again, if you missed it, Assad and allies have killed at least 96% of the civilians killed thus far at nearly 200k (let alone the massacres of Sunni civilians which Assad didn't allow access to)). I'm sure you'd rather I stop showing the atrocities of Assad, but that's not going to happen.
Way less harm to civilians than what has come out of Russia's involvement. Russia is strengthening ISIS, targeting rebels, and killing more civilians than ISIS (and more than they kill ISIS). The US, while being wrong about several things regarding Syria (targeting rebels sometimes, lack of intervention, putting more pressure on the defenders of the majority of Syria than on the killers of the majority of Syria, etc.), has at least targeted ISIS quite a bit unlike Russia.
Quite a bit less than you, though, since I'm not defending the genocidal dictator or his equally evil allies.