After Flo’s and my back-and-forth about this page, I was extremely gratified to see it go up and get mostly positive responses, with some speculation on whether that leg shot would prove to be lethal or debilitating, and extensive commentary from one reader who knew more about guns than I ever have or will.

There are legal, tactical, and responsible-gun-owner angles through which to analyze this moment, but I think the psychology behind Shanna’s action is its centerpiece. Even someone who doesn’t trust a lot of escapist fare has absorbed the popular-culture idea that guns are easy: just point and fire. Clearly, that seems to be about all it takes for any number of mass shooters, practiced or otherwise. But the more wired you are for compassion, the harder overcoming that instinctive resistance to killing generally is.

She thought she’d be ready.