Nike announced that former NFL quarterback Colin Kaepernick will be the new face of its “Just Do It” campaign.

The slogan for the campaign is, “Believe in something, even if it means sacrificing everything.” Kaepernick’s announcement of the campaign instantly went viral Monday after his announcement.

Believe in something, even if it means sacrificing everything. #JustDoIt pic.twitter.com/SRWkMIDdaO — Colin Kaepernick (@Kaepernick7) September 3, 2018

The promotion of the former athlete, who protested racial injustice by kneeling during the national anthem before the NFL games he participated in, has led to major backlash against the sports company. A boycott was started and people began posting videos of themselves burning their Nike gear. Nike stock took a heavy hit for the controversial decision Tuesday morning.

The most scathing critique of the new ad campaign, however, came from the widow of American Sniper Chris Kyle, Taya Kyle. Chris Kyle served as a Navy SEAL sniper during multiple tours in Iraq and was awarded a Silver Star and four Bronze Star Medals. Kyle was tragically killed by a mentally ill man he was mentoring in 2013.

Taya Kyle now raises their two children in Texas and runs a foundation in her husband’s name.

Kyle took to Facebook to level a brutal critique of Nike and their decision to promote a player who has regularly disrespected the American flag. “Sacrificing what exactly? A career?” Kyle asks in her viral post, “At best, that is all Colin sacrificed … some money, and it’s debatable if he really lost his career over it.”

“How about other warriors? Warriors who will not be on magazine covers, who will not get lucrative contracts and millions of followers from their actions and who have truly sacrificed everything,” Kyle asked. “They did it because they believed in something. Take it from me, when I say they sacrificed everything, they also sacrificed the lives of their loved ones who will never be the same. THAT is sacrificing everything for something they believe in.”

Read Kyle’s full message to Nike and Kaepernick below: