Assad isn't the bad guy. He's a secular, only lightly religious agnostic Muslim, a scholar and a doctor of science and medicine. Yes he has killed tens of thousands of jihadi Islamists, and, admittedly, some of their children. But is it better to let them grow up and wage jihad against you for killing their father, regardless of whether their father was evil or not? It's a biological thing, and sometimes you have to cut out the roots so the darn tree doesn't grow back. If you spare the roots the tree often just grows back and becomes an even bigger nuisance than before. The left's precious "humanitarianism" isn't the priority here.