Some sliced the swooshes right out of their socks. Others lit their shoes aflame in their yards and filmed it. All had strong feelings about Nike's new “Just Do It” campaign and one of the athletic shoe and clothing company's newest faces: Colin Kaepernick.

Nike revealed on Monday that Kaepernick — the out-of-work NFL quarterback who generated controversy for kneeling during the national anthem to protest racial injustice and police brutality — would be featured in its 30th anniversary “Just Do It” campaign.

"Believe in something. Even if it means sacrificing everything,” read a teaser for an ad that Kaepernick tweeted.

The ad stood out as a bold statement on racial justice from Nike and as the latest demonstration of the company's values, experts said. While companies often steer clear of taking any firm stance on race relations, experts said Nike has claimed the fight for racial equality as a tenet of its mission.

Kaepernick tweeted what appears to be the full ad on Wednesday. The video showcases athletes who have overcome great obstacles to be among the best in their sports. When the camera pans to Kaepernick, he says "don't ask if your dreams are crazy. Ask if they're crazy enough."

The "Just Do It" ad is set to air Thursday night during the NFL season opener, according to ESPN.

Some Kaepernick critics took that to mean sacrificing their Nike products.

Immediately, people began posting pictures of socks and shoes they had defaced or destroyed, or declaring they would be soon switching allegiances to brands such as Adidas, Brooks or Converse. (Nevermind that Nike owns Converse.)

Country singer John Rich showed off a pair of Nike logos that had been removed from his soundman's socks.

Video of a pair of shoes that had been set on fire went viral.

The anti-Nike puns came next.

"Just Don't,” posted one Instagram user.

"Just Blew It,” posted another.

President Trump has persistently criticized NFL players protesting during the national anthem, a movement Kaepernick launched. Trump and others have frequently mischaracterized Kaepernick's protests as being against the anthem or the American flag.

In an interview with Fox News last year, Trump told host Sean Hannity he thought Kaepernick should have been suspended after his first protest.

"I watched Colin Kaepernick, and I thought it was terrible, and then it got bigger and bigger and started mushrooming. And, frankly, the NFL should have suspended him for one game, and he would have never done it again,” Trump told Hannity, to cheers from a live audience watching the interview. “I will tell you, you cannot disrespect our country, our flag, our anthem. You cannot do that."

Trump weighed in on the Nike campaign Tuesday, telling the Daily Caller that he thought Nike was sending “a terrible message” using Kaepernick in the ads. Still, he acknowledged the company's right to take a stance.

"As much as I disagree with the Colin Kaepernick endorsement, in another way . . . it is what this country is all about, that you have certain freedoms to do things that other people think you shouldn’t do, but I personally am on a different side of it,” Trump told the Daily Caller.

On Wednesday, Trump tweeted stronger criticisms of both Nike and the NFL, repeating his claim that the league's ratings had gone “WAY DOWN” and that Nike was “getting absolutely killed with anger and boycotts."

Nike shares rose in Wednesday morning trading, after closing down more than 3 percent on Tuesday.

The hashtag #NikeBoycott was trending on Twitter through much of Tuesday.

#boycottnike#boycottkapernick

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Morning workout. #NoNike #BoycottNike

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Nike did not respond to a request for comment.

ESPN reporter Darren Rovell, who broke the news Monday, reported Nike's new “Just Do It” campaign would target 15- to 17-year-old s and also include professional athletes Odell Beckham Jr., Shaquem Griffin, Lacey Baker, Serena Williams and LeBron James. Rovell tweeted Tuesday that the NFL did not respond to a request for comment on Nike's decision. In March, Nike and the NFL announced they had extended their longtime partnership for game apparel until 2028.

Late Tuesday afternoon, the NFL released a statement saying the league “believes in dialogue, understanding and unity."

"We embrace the role and responsibility of everyone involved with this game to promote meaningful, positive change in our communities,” NFL spokeswoman Jocelyn Moore said. “The social justice issues that Colin and other professional athletes have raised deserve our attention and action."

As The Washington Post's Mark Maske reported, Kaepernick filed a grievance last fall against the NFL, alleging that multiple teams had colluded to keep him out of the league because of his protests during the national anthem.

The irony of people discarding or defacing their (likely expensive) Nike merchandise to protest something they disagreed with was not lost on those who supported Kaepernick. Many poked fun at the newly declared boycott, even filming satirical videos of themselves “destroying” their own Nike gear in ludicrous ways. Others vowed to wear their Nike apparel more frequently or to buy Nike sports gear to make up for the boycott attempt.

Companies are often pushed to respond to negative publicity or public pressure. But in Nike's case, the Kaepernick ad sends a proactive message on social and racial justice, said Anthony Johndrow, a corporate reputation adviser. The default is to shy away from campaigning on racial issues because companies fear that their own internal ranks may not “stand up to the scrutiny that will come if we take a stance on this,” Johndrow said.

Johndrow said there is a perception that “you’ve got to keep your house in order first” and that companies “can’t go proactive unless they’re pristine.” But Nike is charting another path, Johndrow said, not because the company lacks issues of its own but because it has historically engaged with hot-button topics in its advertising.

In 1995, for example, Nike looked to its “Just Do It” slogan to raise awareness of women’s rights in sports. That same year, the company featured Los Angeles marathon runner Ric Munoz, who was HIV-positive.

Companies decide to take on issues based on how they define their mission, said Sonya Grier, a marketing professor at American University. With that comes the risk of losing those with different views. But that's an inevitable cost of taking on social justice causes, she said. It isn't always as complicated for a company to take a stance on issues like climate control.

But Nike's ad “wades into different water,” Grier said.

Joe Holt, an expert on business ethics at the University of Notre Dame, said there is an important moral difference to companies promoting their views “because you have to” versus “because you want to.” He said one true test of a company's values is if that company is willing to stick to them even at a financial cost. Nike’s use of Kaepernick in the “Just Do It” ad seems to affirm that dedication, Holt said, because it will inevitably alienate some customers.

The Kaepernick ad is not only about racial justice, Holt said, but also tackles civil engagement. He pointed to a meeting between Kaepernick and Nate Boyer, a former Green Beret and football player, after Boyer wrote an open letter critical of Kaepernick's protest. Kaepernick invited him to talk.

Boyer explained that soldiers kneel at the graves of their fallen comrades out of respect. Kaepernick said he would kneel instead of taking a full seat to protest police brutality and the police-involved killings of unarmed black men.

“That is badly needed in our polarized society,” Holt said. “For the most part, people on opposite sides of political questions are talking at each other but not to each other.”

Read more:

Colin Kaepernick to star in Nike’s ‘Just Do It’ campaign

Facing boycott, Laura Ingraham apologizes for taunting Parkland teen over college rejections

‘Just Do It’: The surprising and morbid origin story of Nike’s slogan