Despite making my home in the U.S. more than a decade ago, I still share the bewilderment of outsiders when it comes to mass school shootings. It is a peculiarly American disease and one that the political establishment appears unable or unwilling to address in any meaningful way.

And it never gets easier to comprehend. Trying to make sense of why an 18-year-old gunman would walk into a school and shoot dead 19 kids and two adults is, in any ways, futile. But we can try and bring context to what happened. And that is what criminologists James Densley and Jillian Peterson have done with their article looking at the rise of mass school shootings in the U.S.

Such is the frequency of this uniquely American problem, that Densley and Peterson have been able to build a database of mass public shootings and with that a profile of the gunmen involved. “Their path to violence involves self-hate and despair turned outward at the world. The key to stopping these tragedies is for society to be alert to these warning signs and act on them immediately,” they write.

Of course, many people outside the U.S. will suggest there is a different “key” to preventing such atrocities: gun control. Why, even after the mass murder of children, such measures tend to fail – with some states even loosening their gun restrictions – will form the basis of two articles due to be published later today.