If you join tens of millions of other Americans today by turning on a football game, think for a moment about Mike Webster, the tough-guy center who anchored the great Pittsburgh Steelers teams of the 1970s.

Think of Iron Mike especially if you’re the parents of kids who aspire to emulate their heroes.

Webster is one focus of “League of Denial,” a PBS-Frontline documentary that aired last week about head injury and dementia among retired football players. Webster died in 2002, broken at age 50, in Pittsburgh.

Pathologist Bennet I. Omalu, then working in the Allegheny County Coroner’s Office, discovered why Webster in his final days could no longer remember his way to the grocery store and slept in his car: chronic traumatic encephalopathy, a degenerative brain disease linked to repeated hits to the head.

Too often, the National Football League has failed to acknowledge the connection between head trauma suffered by some gladiators who play the game that American so loves, and dementia later in their lives.

Frontline based its documentary on reporting by brothers Steve Fainaru, who won a Pulitzer Prize for his Iraq coverage while working for the Washington Post, and Mark Fainaru-Wada, who helped break the BALCO steroid scandal. Their book, “League of Denial: The NFL, Concussions and the Battle for Truth,” was published last week.

The NFL, a master at public relations, has tried to spin its way out of the problem. The league ought to devote at least as much energy to solving the problem of repetitive head trauma as it does trying to persuade its fans that there is no story here.