Editor's Note: This article is one of 50 in a series about Trump's first two years as president.

The exact date I knew that Colin Kaepernick would never play in the NFL again was March 20, 2017. That day, Donald Trump held a rally in Louisville, Kentucky, and publicly eviscerated Kaepernick—who had been taking a knee during the national anthem to protest the treatment of people of color by police and the criminal-justice system—for the first time as president. He had gone after the athlete many times on the campaign trail, but with the power of the Oval Office behind him, this became an even more potent takedown.

Trump referred to Kaepernick as “your San Francisco quarterback—I’m sure nobody’s ever heard of him.” He also bragged about the fact that he was responsible for NFL owners’ not signing Kaepernick, a free agent at the time, because they feared a public rebuke from Trump. Although the president has lashed out at Kaepernick since Louisville (including criticizing Nike for making Kaepernick the face of an ad campaign in September), it was Trump’s Louisville comments that were especially significant.

Trump’s remarks were essentially a smoking gun for Kaepernick’s collusion case against the NFL, which an arbitrator ruled in August could proceed to a full hearing. A few months before the ruling, The Wall Street Journal obtained depositions in the case showing that Trump successfully scared the bejesus out of NFL owners. That isn’t easy to do. The Dallas Cowboys owner, Jerry Jones, stated in his deposition that Trump told him the NFL protests were “a very winning, strong issue for me. Tell everybody, you can’t win this one. This one lifts me.” Jones reportedly relayed that message to his fellow owners, and suddenly the Miami Dolphins owner, Stephen Ross, who had created a grant program for social-justice organizations, was having an epiphany. Ross admitted under oath that he was initially supportive of the protests, but that Trump’s comments changed his mind.

The real irony is that as Trump has gleefully claimed victory for forcing Kaepernick’s unemployment, the president also may have gift-wrapped a winning case for the athlete at the NFL’s expense. Considering how much Trump loathes the NFL for blocking his ownership attempts in the past, that’s karma to an infinite power.

Trump possesses a unique ability to change narratives, and he has been able to use black athletes as a perfect foil. In September 2017, at a rally in Alabama, he said NFL owners should react to protesting players by saying, “Get that son of a bitch off the field right now. He’s fired. He’s fired!” That same year, he disinvited the Golden State Warriors to the White House after they won the NBA championship, because Steph Curry had admitted that he didn’t want to be near Trump, which led to LeBron James calling the president a “bum” in the seventh-most-retweeted tweet of 2017. In those instances, Trump painted African American athletes as ungrateful, all to the thunderous applause of his base.

Trump isn’t the first president to show such overt interest in sports, but he’s the only president in recent memory to weaponize sports as a divisive political tool. It cost Colin Kaepernick his career, and NFL owners their self-respect.

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