With each bone-breaking, head-injuring hit, NFL players are killing themselves slowly. It’s not a possibility. It’s a fact, no less certain than the league’s immense profitability.

Football injuries can kill in a variety of ways. One particularly tragic way might be by making life unbearable for the afflicted. And autopsies have revealed that several former players who committed suicide suffered from brain trauma caused by repeated blows to the head.

It’s unclear why former San Diego Chargers linebacker Junior Seau shot himself in the chest last week. There’s no proof, yet, that Seau even suffered from trauma-induced brain damage, much less killed himself because of it. But it’s a good bet it was on his mind.

Why does a man choose to shoot himself in the chest instead of the head? Possibly to preserve evidence of the toll an NFL career takes on the brain. I believe Seau, who was just 43, wanted to deliver a final message, one that would force us to ask uncomfortable questions. And if that was his goal, he clearly succeeded.

Others in the media are holding the NFL accountable for its part in this tragedy. No need for me to pile on.

Instead, I want to pose another, even more uncomfortable question that has escaped much contemplation: How much responsibility does the football-loving public share in the physical devastation endured by players? We revel in highlight-tape hits, yet we know the object of our delight leads to life-destroying pain. Each time we applaud young men for knocking heads with reckless abandon, we’re possibly dooming them to early death, or a life so miserable they will be driven to end it by their own hand.

With everything we now know about how the body responds to the NFL workplace, continuing to support the league has become a question of morals. Ticket-buying, television-watching fans provide the fuel for the professional sports’ second-to-none money-making machine (the league generates about $9 billion annually in revenue).

Big-play excitement against a backdrop of controlled mayhem is what draws fans and keeps them coming back. Without that element of chaos, the NFL’s perch surely would not be so lofty. Although most of us may choose not to admit it, the violence is one of the league’s biggest lures. That’s what many of us crave.

In a sense, we’re like the ancient Romans. Essentially, NFL players are modern gladiators. In front of huge crowds, they fight each other for the public’s entertainment, at great peril to their health.

The object is basically the same as it was thousands of years ago: to physically dominate your opponent into submission. So are we no better than the bloodthirsty crowds that filled the Colosseum?

The Romans didn’t have the benefit of understanding the horrors of Chronic Traumatic Encephalopathy, or CTE, as it’s commonly known. The progressive degenerative disease, discovered in the brains of some deceased former NFL players, is associated with memory loss, confusion, impaired judgment, impulse control problems, aggression and depression. Studies also have determined NFL players suffer from Alzheimer’s disease and other forms of dementia at a much higher rate than the rest of the population. Even top athletes can’t absorb what some physicians describe as low-impact car crashes on every play without it eventually taking a toll.

The league is facing a growing number of concussion-related lawsuits that include more than 1,300 former players.

None of this can come as a surprise to most active players, who, though aware of the risks, continue to expose their bodies too hard for the game’s rewards — more money in a few seasons than most of us will earn in a lifetime, money that exists because we watch in ever increasing numbers.

A small percentage of NFL players, however, do leave the game even when they’re at the top of it. After playing running back for 10 seasons for the New York Giants, Tiki Barber retired in 2006 at age 31.

Despite finishing fourth in the league with 1,662 yards, Barber walked away because “it was my long-term health I was thinking about,” he said in a phone interview Friday. “It really wasn’t in the vein of mental health because of concussions and of Chronic Traumatic Encephalopathy and all that stuff that’s starting to come out so much now. I simply wanted to be able to walk and play with my kids.

“But as I’ve gotten a little bit more knowledge about the concussion issue that’s becoming an epidemic, it makes me worry, as a former player, ‘Is that going to happen to me in 10 years?’ But also, for me, it verifies why I walked away. . . . Given the violent nature of my position, I’m sure these things would have affected me.”

Seau committed suicide in a similar manner to that of longtime Pro Bowl safety Dave Duerson, who suffered from CTE and shot himself in the chest just last year. Before he picked up a gun and aimed it at his heart, Duerson texted his family, asking that his brain be given to medical researchers studying CTE.

To be sure, no one forced Seau and Duerson to become NFL players. While the long-term hazards were not as evident as they are now, players have long been aware of the game’s violence, and may have even reveled in elements of it. They received wallet-stuffing paydays for their efforts and enjoyed lap-of-luxury lifestyles most people experience only in their dreams.

But does that absolve those of us screaming from the bleachers? To be more painfully specific, does it absolve me, who has spent much of my career not only watching NFL games, but profiting from them?

My work as a beat reporter, and now as a columnist, helps glorify the thrill of a violent sport, and perpetuates the economic engine that fuels it. I still can’t shake the unsettling feeling that it’s wrong for me to contribute to something I know inflicts so much pain on others, some of whom I count among my friends.

For his part, Barber believes fans’ responsibility extends only to their own families.

“They should inform their children about the dangers of the game. That part is on them,” he said. “But that’s it. I don’t think the downstream effect of what happens to players is on them.

“It’s a form of entertainment. We love the game because of the brutal nature of it and the excitement. That’s why fans watch.”

I’ll continue to watch as well. But that doesn’t mean I’ll feel good about it. Or that I should.

For Jason Reid’s previous columns, go to washingtonpost.com/reid.