Even if I assume that the people being destroyed in Aleppo are remotely better than Assad, let alone our friends in any meaningful sense (which I don't), what are we supposed to do? Send in the troops? Watch how quickly those same civilians will spit on us and call us war criminals when a stray bomb from one of our forces kills anyone.

There is zero evidence that the alternative to Assad is an improvement over him, and every reason to believe that it will be a good deal worse. Sometimes when every option is bad, the only good option is to do nothing.

We learned our lesson from Iraq, Lybia, Syria, Somalia etc... The Syrians will have to figure this out for themselves.