A glaring difference is who it was used against. Assad used it against his own people with no(as far as I am aware)military presence. We used napalm against a military enemy, civilians gat it too but in that conflict you have to look at the enemy, they blended into the civilians with no way to tell the difference. So all we could act on is intelligence, the ones to blame for civilian casualties would be them for using human shields.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!