Want to stop these riots? Reform the police.

Every Fourth of July when I was a boy, the Jaycees sponsored a carnival at our local park, followed by a concert from the town’s volunteer band and a fireworks show. The water-balloon toss and the cotton candy machine were delightful, I suppose, but the attraction that galvanized every boy at the fair was the chance to lay down two bucks for the chance to swing a sledgehammer at an old car.

This was big money in those days. An hour and a half mowing and trimming a neighbor’s lawn would buy only two swings (plus a hot dog). The younger boys could barely lift the hammer. But there was always a line. And it was longest when there was still glass to be smashed.

I thought of that grand civic tradition as I studied a photograph from the rioting in Minneapolis. The camera caught a young man with a hammer as he took a whack at a cashier’s scanner inside a looted Target store. Destroying the property of innocent people is wrong and, as a form of political protest, it is usually self-defeating. But I couldn’t deny the visceral appeal of putting that hammer through that glass. Destruction speaks to something in the human back-brain, the seat of anarchy, the root of unruliness.

The satisfaction of swinging the hammer has nothing to do with race or class. If kids in the richest, whitest part of the Twin Cities were invited to whale away at a surplus cashier’s scanner, or most anything else, there would be plenty of takers. Riots become riots because the initial violence gives a kind of permission to indulge the limbic urge to destroy. Breaking windows is contagious; so is setting fires, upending cars and emptying store shelves.

For this reason, the time to stop a riot is not when flames are dancing to the crash and tinkle of shattering glass. Riots must be stopped before they happen. It’s all about prevention. Nearly six years after Ferguson — and close to 55 years after the Watts riots in Los Angeles — the United States still has not taken the obvious preventive measure of consistent, top-to-bottom police reform.