Mitt Romney has a problem.

Yesterday the Washington Post reported that in 1965, when he was a high school senior, Romney organized a group of his fellow students in a physical assault on a gay classmate, John Lauber. When Lauber, who was closeted at the time, appeared on campus one spring wearing his hair longer than usual, and dyed blond, Romney reportedly put together a posse who grabbed him and held him down, screaming and crying, while Romney cut his hair with a pair of scissors.

Four of Romney’s classmates confirmed the story to the Post, including one who says he participated in the assault.

Of course, 1965 was a long time ago, and few of us would want to be judged on the basis of our worst moments in high school. But this was a physical assault, an act of bullying that participants and witnesses remember as “senseless” and “vicious.” In the era of Tyler Clementi and “it gets better,” it’s an incident that demands a response.

There are three ways to address a story like this. The first, obviously, is to deny it, which Romney doesn’t do. He says he doesn’t remember it, but doesn’t dispute that it happened. That leaves two choices: acknowledge that the incident was serious and express real remorse, or dismiss it as insignificant.

You can’t do both. If the attack was wrong, you can’t brush it aside. Non-conforming kids are still getting brutalized today, and you can’t stand up against that kind of bullying if you don’t take it seriously in your own past. Conversely, any defense that rests on a claim that the story isn’t important because Romney has evolved as a person since high school has to be accompanied by some indication of what that evolution has entailed.

So far, Romney has tried to blow the story off. He’s offered a variety of conditional, vague apologies, but ducked a reporter who asked him whether he’d characterize the incident as one of bullying, and giggled his way through the first interview in which the issue came up. He’s going through the motions of expressing contrition, but making it clear that he’s eager to move on to more serious issues.

And his supporters are following his lead. Victor Davis Hanson at the National Review has dismissed the story as “silly” and “trivial.” A Breitbart columnist has gone so far as to suggest that Romney was merely enforcing the school’s dress code.

I don’t think this approach is going to fly. Teen violence is a recognized problem in this country, and Romney’s equivocation gives comfort to its apologists. On the National Review website, one commenter declared that “we all have such episodes in our past,” while another suggested that the story “makes it sound like he was a normal red-blooded American male teenager and makes him more likable.” As long as Romney continues to minimize his actions, he’s effectively endorsing these defenses and normalizing his behavior.

And it’s not normal behavior. Romney and his friends terrorized this kid. They violated him, punishing him for his non-conformity. Romney has characterized this as “hijinks” that “might have gone too far.” But that’s not what it was. It was a violent assault. An act of cruelty against someone smaller, weaker, less favored. As a matter of basic human decency, Romney should acknowledge that. As a matter of politics, his failure to do so is likely to hurt him with folks who identify more with his victim than they do with him.