Assad is particularly criminal for his forces' use of "barrel bombs" which lack the sleek lines, rakish fins, and elegant paint jobs of the bombs that the U.S. planes drop in Syria. These barrel bombs apparently contain shrapnel, which is unheard of in the history of explosive ordnance. (Here are some video clips of barrel bombs being used against civilians, some bombs falling in the vicinity of the positions of "civilians" yelling "Allahu ahkbar" and manning heavy-caliber machine guns [4:20].)
Anyway, this bombing is considered "indiscriminate" and is causing much angst in the ranks of the State Department and Defense Department.
Contrast that with the U.S.-supported Iraqi attack on Mosul that began yesterday. There it's a much different matter as Military Necessity appears to take precedence, and for the civilians still in Mosul it's sauve qui peut, baby. An ex-U.S. Special Forces gentleman was on Fox last night (Kelly?) talking about possible civilian casualties and he made the observation that "we can't tie our hands" beforehand when conducting operations of this kind. That's actually true. The purpose of military operations is to find, fix, and destroy the enemy, not to conduct social welfare campaigns.
Check out this short video of French artillery supporting the attack on Mosul and ask yourself if it's likely that the commander of that unit even knows where ISIS troops can be fired on without injuring civilians. Do you think the safety of civilians in Mosul is his primary concern?
Urban warfare is every infantryman's nightmare for the unlimited cover available to the enemy behind every wall or window. Clearing and holding urban real estate is not an exact science conducted with laser beams and algorithms that identify which buildings shelter the enemy. But that exactitude is required only of Syria and Russia. It's an impossible and unrealistic requirement. The breast beating about indiscriminate bombing of civilians and "barrel bombs" is just Academy Award-level fake outrage.
 Innocent civilians, of course, as all guilty civilians have already made their unimpeded way from E. Aleppo for the safety of W. Aleppo, where they are shelled by the al-Qaida franchise still in E. Aleppo. We bring clarity to a confusing situation.
 FoxNews and CNN emphasize that barrel bombs also fall on wakes, aid centers, refugee camps, and hospitals and deliver chlorine gas. Very possibly true in some instances though verification is in order. (I doubt all attributions of the use of gas to Assad's forces, let it be said.) Note, however, that the issue, even assuming all these civilian casualties (excepting gas casualties), is what standard applies? The video in second paragraph is part of the discussion as well, just as much as the attacks described in this footnote.