Why do you care so much about school shootings specifically? Shouldn’t be the goal to reduce overall child mortality? In which case it doesn’t make sense to focus on school shootings. They’re a rounding error in child mortality. Compare actual death rates between first-world countries to see what I mean; the US lags behind its Western peers, but the presence of school shootings, which is generally referred to as a decidedly American problem, is not nearly large enough to make an appreciable difference [1].
It's about empathy. Publicly stating that you are concerned about children being shot shows empathy and boosts one's image.
Publicly stating that you are concerned about child obesity is dangerous because it's implicitly stating that people are raising their children incorrectly and making poor decisions, which is more of an accusatory than empathetical statement.
The "think about the children" crowd don't actually want you to think about the children.
Maybe because I'm from one of the countries that doesn't have school shootings, so everytime I see that shit on the news I think I sure am relieved I can send my kid to school and not have that particular anxiety hanging over me. It's just so senseless. It's less about the raw numbers and more about how bloody horrific such an event is for everyone involved.
The fact that there are school shootings for the media to report on at all is so crazy to me.