Gun-control advocates tend to react to shootings — especially mass shootings — with impulse and emotion. In their haste to demand that government do something, anything, no matter how ineffective, they tend to call for solutions that are either unresponsive to the problem or already demonstrated failures.

Take universal background checks as an example. Although these could probably be legislated in a way that respects gun owners’ privacy and the Second Amendment, there is no evidence that any significant amount of crime is committed using the very small minority of guns whose sale would be affected — i.e., intrastate purchases in the 31 states that do not already require a background check. We are not aware of even one mass shooting committed with such a gun, and we doubt that many such guns are used in common crimes either. In short, universal background checks are an attainable but not very useful idea. They wouldn’t prevent much violence.