It’s not just the shootings, but the whole response to it.
Do I want to bring my kids to a country where they will likely be trained to believe that someone may come into their school in order to gun them down? Do I want to instill in then the idea that in their home culture, they have to actively train themselves and their classmates for a situation in which one or more people may hunt them down and kill them in cold blood?
When my family and about going back to America, I just tell them I can’t imagine putting my kids into that kind of culture.