Before Colin Kaepernick knelt and Marshawn Lynch squatted in righteous protest, Doughboys were dying in the muddy trenches of France as World War I consumed 18 million lives in a toxic stalemate that married American sports to the “Star-Spangled Banner.”

A century of reflexive nationalism is enough. It is time to divorce the games that entertain us from their compulsory salute.

Want to keep our venomous politics from pouring over the firewalls of our stadium sanctuaries and flooding our fields of play? Cut out the middle man. Save the anthems for the Olympics, the postseason or national mourning.

Uncle Sam loves sports. He glorifies winning. And he venerates war.

Lest anyone forget, Francis Scott Key’s lyric is a battle hymn written in the bloody aftermath of a British attack in the War of 1812.

It had never been played at a sporting event until the 1918 World Series between the Red Sox and Cubs.

Seventeen months after the United States entered the “war to end all wars,” more than 100,000 Americans had been killed in action.

Players were being conscripted to fight overseas. The country was on edge as wounded amputees and shell-shocked soldiers returned maimed by chemical and mechanized war more destructive than anything in human history.

During the seventh-inning stretch in Game 3 at Wrigley Field, a military band struck up the “Star-Spangled Banner.”

Red Sox third baseman Fred Thomas was playing the Series on furlough from the Navy. Thomas turned and snapped to attention with a military salute, according to a 2011 ESPN.com story. The crowd, which already was standing, sang along.

It was an organic display of patriotism that touched a nerve the national press celebrated. And a tradition was born that continues at rinks, courts, racetracks, ballparks and stadiums everywhere.

Kaepernick, Lynch and the growing chorus of NFL players spotlighting racial injustice have inalienable rights to lash out against inequalities that have plagued us since slave owners in the white wigs conquered Native Americans in the name of freedom and democratically scripted this beautiful, hot mess we call the United States.

They already have massive megaphones to amplify their cause on social media or from whatever late-night couch and ESPN scream fest they choose. Lynch has daily access to a bank of microphones as a running back with the Oakland Raiders.

Kaepernick undoubtedly has been blackballed by 32 yellow-bellied NFL owners unwilling to employ a Super Bowl quarterback lest the knuckle-dragging masses howl.

This cabal is so collectively paranoid about signing a radical with an Afro to back up their starter they would rather have a slab of beef named Ryan Mallet (Baltimore), some 38-year-old fossil like Josh McCown (New York Jets) or a remedial passer such as Dan Orlovsky (L.A. Rams).

Dan Orlovsky still earning an NFL paycheck is jaw-dropping. Five teams, 12 career starts and a 2-10 record. He was responsible for seven of the 16 losses the winless Detroit Lions racked up in 2008, when Orlovsky once ran 5 yards out the back of his own end zone at the Metrodome for a safety that etched his Google epitaph.

Kaepernick’s greatest sin was protesting police abuse and a rigged system in an arena governed by NFL sharks with the moral compass of a reality TV star in the White House.

Remember how skittish the Philadelphia Eagles were about signing quarterback Michael Vick after his dog-fighting conviction? Front-office frauds were practically standing outside the prison gates with a contract in hand, eager to empower a felon whose training methods included beating and chaining dogs to trees when he wasn’t drowning the losers.

Give me your tired wife beaters, your poor child abusers, your huddled drunken-drivers yearning to catch touchdowns and leverage guaranteed money from a league content to selectively look the other way.

Kaepernick, Lynch and others have the (gasp!) audacity to point out police abuse and the deck stacked against underprivileged minorities during the solemn pregame serenade of our war-mongering military industrial complex.

So snuff the anthems. Disarm the provocateurs. Go back to staring at your cell phones and paying for $12 beers while awaiting first pitch or kickoff.

Before Wednesday’s Twin-Indians game, the band from Moorhead Public Schools played the “Star Spangled Banner” with the tarp on the field, the lower bowl mostly empty and not a single player from either team in the dugout.

Pity the poor sap who strikes out with the bases loaded Sunday afternoon and has to maintain a stiff upper lip during “God Bless America,” another feel-good tradition watered down since it debuted during our post-9/11 grief.

Forget rote rituals. Give me real emotion like veterans raising the flag at Target Field or military families unexpectedly reunited with their soldier spouses and parents.

They deserve our unbridled attention.