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Some decades from now, maybe even longer, many Americans will look back at this day—September 24, 2017—as one of the most important moments in the nation's history.

This is not hyperbole. This is not overstatement. This is a fact.

It will be seen as a day when a president attempted to bully a professional sports league, make its players kowtow, bend the knee to his desire.

Instead, they took one. By the hundreds.

President Donald Trump thought he would intimidate the NFL, and use race as a wedge. On Friday, he urged owners to "fire" players who knelt during the national anthem. He doubled down on his rhetoric Sunday morning, calling for fans to stop attending games until players stop kneeling.

Players responded with one of the more important peaceful protests this country has ever seen.

The entire Seahawks team refused to appear for the pregame anthem. Same with the Titans. Then, the singer herself took a knee at the end of her performance to a pair of empty sidelines. The singer in Detroit did the same.

Steelers players stayed in the locker room in Chicago during the anthem. Only a former Army veteran, offensive tackle Alejandro Villanueva, was present for the team.

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Nothing like this had ever happened before in league history. In sports history.

One league official, who said he watched the beginning of a number of games, estimated that 300-400 players protested. He was including players who knelt, sat, locked arms or stayed in the locker room. My guess, after watching a number of the protests, is the number is closer to at least 500. The NFL has about 1,600 players total.

Chargers players locked arms while defensive end Melvin Ingram knelt. In London, at least 12 Jaguars players took a knee. The owner of the team, Shahid Khan, who donated $1 million to the Trump inauguration, stood arm-in-arm with his players on the sideline during the anthem. About the same number of Ravens players, including future Hall of Famer Ray Lewis, who had a meeting with Trump, also took a knee. Three Packers players took a seat on the bench as the anthem played. Dolphins owner Stephen Ross locked arms with his players.

Stars and non-stars alike protested. Aaron Rodgers interlocked arms with his teammates after posting a photo on Instagram of him kneeling with other Packers accompanied by the hashtags "#unity #brotherhood #family #dedication #love." Dolphins players warmed up prior to the game wearing "I'm With Kap" shirts, and safety Michael Thomas got emotional when speaking of Trump. The Chiefs' Travis Kelce took a knee. Even Darrelle Revis, who isn't in the NFL at the moment but is a Hall of Fame candidate, spoke about Trump in a statement released on Twitter.

Indeed, there was no star system today. Just players protesting together.

Giants defensive lineman Damon Harrison wrote about his children, and their future, in a statement he posted on Twitter.

When dozens of Browns players knelt in Indianapolis, they got a round of boos from some Colts fans. Ten Saints players knelt as well. In New England, 17 players took a knee. Some fans booed them as well.

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But on and on came the responses from players and the league. The NFL released a unity video. Even legendary members of the media, like Dan Rather, chimed in. At the end of the day, another striking image. About 30-40 Raiders players sat with arms interlocked.

All in all, Sunday will be remembered as one of the greatest social justice moments in sports since Tommie Smith and John Carlos raised their fists at the 1968 Olympics. Coincidentally, after scoring a crucial touchdown, Odell Beckham raised a single fist.

This was a day that showed that Trump's attempt to divide the NFL, and ostensibly America, might have backfired.

Denver pass-rusher Von Miller, when asked by reporters why he took a knee during the anthem, responded: "We felt like President Trump's speech was an assault on our most cherished right, freedom of speech."

"I think he's wrong and it sucks we have to listen to that crap," Giants linebacker Jonathan Casillas said.

"I can't stand and support something where our leader is acting like a jerk," Bills running back LeSean McCoy told the press.

"I thought it was huge for this team, for this organization, for America," said Texans cornerback Kareem Jackson, speaking of the protests.

Bills linebacker Lorenzo Alexander, in a statement worth listening to, said what finally pushed him was the president "calling some neo-Nazis and KKK members fine people," while calling peaceful NFL protesters "son of a bitch."

That notion—wherein Trump portrayed NFL players as thugs but white supremacists as decent people—remains the core of why players did what they did.

"I'm disappointed in the comments that were made," Saints coach Sean Payton said. "I think we need a little bit more wisdom in that office."

In addition to the massive protests, many of the crucial early games were brilliant and entertaining. It was almost as if the entire NFL gave a giant middle finger to the president of the United States after he tweeted about its "boring" games Sunday morning.

So, after all of that, the question becomes: Now what?

In the short term, the NFL is now definitely part of the culture wars, and it likely will stay that way throughout the Trump presidency. Opponents of the protests will continue to say they are un-American; proponents will say protesting is as American as apple pie and Star Trek. The league even made it onto the Sunday political shows, when Treasury Secretary Steven Mnuchin told CNN the NFL should have a national anthem rule. Mnuchin didn't say what that rule should be.

What happened this weekend will set the tone for the weeks ahead. Players interviewed believe this will lead to a tighter player base, one that could end up closer and more activist than at any other time in league history.

That's almost a guarantee. Players weren't unified during two strikes in the 1980s, a lockout and many other things. But in this moment, and maybe more so than at any time in the history of the NFL, the players were unified.

That won't change anytime soon.

And it's probably just the beginning.

Mike Freeman covers the NFL for Bleacher Report. Follow him on Twitter: @mikefreemanNFL.