In November 2015, a movie, "Concussion," changed public perception of American football forever. It told how professional players were suffering a disabling and progressing brain disease, called chronic traumatic encephalopathy (CTE) and how the NFL had tried to block the science from emerging. The film hinted that CTE might start even with school-age tackle football. Dr. Shailey Prasad and I reviewed the science and found that there was good reason to fear brain damage from school tackle football. We argued for a middle position, one that did not criminalize football but that would move teams and leagues outside of schools to extramural teams, where most young people play anyway.

The reaction to that modest proposal was explosive. Since then, peer-reviewed studies have shown that head trauma during school football, even when it does not produce the symptoms of concussion, damages the brain. The damage accumulates. It can be seen on brain scans and autopsies of young players. The severity of damage is correlated with reduced academic performance. The longer a person plays, the more damage occurs. Industry-supported experts vigorously disagreed and said that rule changes and heads-up tackles — which have never been found to be beneficial — were all that was needed.

Minnesota parents are beginning to keep their children from playing tackle football.

For the 2014 and 2015 seasons, 356 Minnesota high schools had 11-player tackle teams with 23,794 and 23,751 players. Midseason in 2015, the movie and the national debate happened. In 2016, National Federation of State High School Associations data show that 11 fewer Minnesota schools had teams and that the number of players dropped to 23,170. It is reasonable to surmise that more parents will keep their children from playing tackle football in the future as the culture changes. The decline in the number of high school football teams will accelerate as the loss of schools affects the opportunity for league play.

Parents in other states are making similar choices. In Massachusetts, for example, there were 1,200 fewer players last season. The decline in the number of players will drastically affect recruiting by college programs, especially in the NCAA's Division II and III.

For most students, football is a spectator sport. High school physical fitness programs should allocate resources toward activities that can be enjoyed by nearly all people for their entire lives — sports like jogging, workouts, basketball, tennis or bicycling. There is no reason for schools and parents to accept the relatively high risk of damaging students' very brains.

DR. Steven Miles, Minneapolis
CONFEDERATE MEMORIALS

Should we tear these statues down — or leave them up?

I don't agree with much of Donald Trump's philosophy, but I think he's right about the statues ("Trump bemoans removal of 'our beautiful statues' in new tweets," StarTribune.com, Aug. 17). The Civil War happened. It is not an "alternative fact." Robert E. Lee, Stonewall Jackson and the other Confederate generals did exist. To take all these statues down is like trying to erase history. However painful it may be for some, erasing history is impossible. "When will it end?" Trump asks. George Washington was a slaveholder, as was Thomas Jefferson. Should we take down their monuments, too?

Bill Arthur, Hopkins

• • •

The statues to the Confederate generals are an abomination. These people were traitors and took arms against the U.S. Their actions resulted in hundreds of thousands of dead soldiers and civilians. There is no place for honoring these people. They were racists and fought to keep people in slavery. The statues all must be taken down. They have been symbols of oppression, treason and hate. Robert E. Lee said he wanted no statues of himself and there should be none to any Confederates. They will cause people to be trapped by these ideas. People will move on faster if there are no symbols of the Confederacy.

Take them down for now and ever.

Ronald Hegner, Independence

• • •

Recent events have called attention to the Confederacy and the statues in many Southern cities that symbolize that era of U.S. history. Many Americans see these statues of, for example, Robert E. Lee and Stonewall Jackson as icons of slavery and want to see them removed. I count myself among those who are astonished that such landmarks are still standing.

If Southern whites are upset about the removal of these "symbols of Southern heritage," by all means, leave them up. If they're so concerned that people will forget about the glory days of this country prior to the mid-19th century, keep them standing, but educate those who come to view. Add a very visible plaque that explains exactly what these men stood for: a morally repugnant, indefensible, vile institution of slavery that robbed individuals of freedom and dignity. Anyone who owned slaves or otherwise supported this institution debased themselves. They were adherents of a reprehensible ideology that disgraced the entire country.

So, yes, keep Mr. Jefferson Davis upright on a pedestal and inform all observers of the sickness that he symbolized. Let us not forget.

Jill Schwimmer, Minneapolis
CEOs AND TRUMP

3M chief didn't speak out enough in quitting council

Your unqualified editorial praise of 3M CEO Inge Thulin's resignation from President Trump's Manufacturing Advisory Council seems misplaced ("3M CEO leads while Trump inflames," Aug. 17). Thulin waited more than a day before joining several other corporate leaders who had quit the panel in protest of Trump's statements about the violence in Charlottesville. Moreover, Thulin's explanation of his belated move never directly mentioned racism as a compelling factor in his decision. Nor did he criticize Trump by name. Instead, the executive said the council no longer was "an effective vehicle" for his company.

A 3M shareholder, I have long admired the corporation's reputation — stated in Thulin's official bio — as "among the world's most admired, most respected and most ethical companies."

Given the stark issues involved this past weekend, I am disappointed that the CEO failed to address them directly or cite them as the primary reason for his resignation.

Richard Gibson, Battle Lake, Minn.
SUN COUNTRY AIRLINES

You've got to be kidding me

More disturbing than crushing his customers closer together on flights with added seats or charging for carry-ons are the decisions of the new CEO of Sun Country Airlines of forcing older employees out for "younger and cheaper" ("New path charted for Sun Country," Aug. 17). Exactly the reason I always chose my hometown airline for the seasoned, friendly devoted employees. Probably no more.

Roger Kiemele, Minneapolis