Arab societies are based on the family and clan. If one guy is involved, that means at bare minimum, the family (particularly elder males) are very well aware of it, more likely they are all involved in direct support.
Also, the author’s indirect argument that we need to keep troops in Syria so we can kill Jihadis without hitting their family is asinine.
Too many armchair strategists seem to be oblivious to two points. 1. Who made the case for what the US is doing in Syria when? 2. If you want support from the American public for the Rules of War, they need to understand why those rules are there and how those rules help the US win.