From Muhammad Ali to the Black power salute at the 1968 Summer Olympics to Colin Kaepernick, sports have long brought attention to political and racial concerns of the times. The Bucks' stand over the shooting in Kenosha, Wisconsin, just 40 miles from their home arena, continued that activism and inspired similar responses across the league, the WNBA and professional baseball, soccer and hockey.
"Despite the overwhelming plea for change, there has been no action, so our focus today cannot be on basketball," the Bucks' players said in a joint statement Wednesday night before their scheduled game against the Orlando Magic.
Several NFL teams canceled their practices, and biracial tennis player Naomi Osaka announced that she would not play her Western and Southern Open semifinal match Thursday.
"In some ways, this is similar to the climate of the '60s and early '70s, in which there was this Black nationalism, this incredible activism, which actually pulled athletes into the Black freedom struggle and also opposition to the Vietnam War," said New York University history professor Jeffrey Sammons, an expert on race and sports.
But 2020 is also different, he said.
"It's become clear that athletes have considerably more power than they did back then, and I think what's happening in the larger society has given them more cover than they have had before," Sammons said.
The national reckoning over race was galvanized by the death on May 25 of George Floyd, 46, a Black father of five, under the knee of white Minneapolis police Officer Derek Chauvin. Cellphone video of Floyd's death prompted millions of Americans to take to the streets during the coronavirus pandemic to protest racism, police brutality and mass incarceration of Black people.
The resulting boost to the Black Lives Matter movement bolstered demands for police reform, led to the filing of criminal charges against officers accused of brutality and toppled Confederate monuments, among many issues at the forefront of current activism.
Professional athletes, however, have a unique platform to spread that message more widely than even Black politicians and activists, because their popularity cuts across so many racial, generational and political lines.
"Now that we have the calibration that's done by social media followers, we know where LeBron James stands in terms of popularity and influence, so there's a greater acknowledgment that they have they this platform," said Kenneth L. Shropshire, CEO of the Global Sport Institute at Arizona State University. "And they've accepted that they have this platform, as well."
James, the Los Angeles Lakers superstar, boasts 141 million followers across Instagram, Twitter and Facebook.
The momentum for Wednesday's walk-off may have been boosted by the pandemic, which led to most of the NBA's superstars' playing and living together in a Florida "bubble."
"Somebody said it's kind of a herd immunity," said Shropshire, author of "In Black and White: Race and Sports in America." "The idea that in this moment, because they're all there together in this bubble, that there was just more unity in deciding to do this."
The WNBA has been ahead of the NBA over the past few years, Shropshire said, pointing out that its players association was the first to ask him to speak about what players could do as sports celebrities to promote racial justice after Trayvon Martin, 17, who was Black, was fatally shot by a white man in 2012.
One of the league's biggest stars, Maya Moore, walked away from the game for the past two seasons to dedicate her time to fight for the release of a Missouri man who spent 23 years in prison for a crime he says he did not commit.
Because sports strikes have traditionally been sparked by labor issues, there is little historical precedent for the unified action taken this week around a non-sports cause, Shropshire said. A rare exception, he said, was the 1965 American Football League All-Star Game, which had been set to take place in New Orleans. When Black athletes were stranded at the airport because taxi drivers in the segregated city refused them as fares, enough players threatened to boycott the game that the league moved it to Houston.
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Yet over the decades, individual athletes have paid a price for speaking out about social justice issues. The cancellations of games Wednesday came four years to the day after Kaepernick took a knee for the first time during the national anthem to protest a recent spate of police brutality against Black men.
The silent act by Kaepernick, then the quarterback for the San Francisco 49ers, led to loud backlash from conservatives who said it disrespected the anthem, and Republican presidential candidate Donald Trump seized on it as a campaign issue. Kaepernick was dropped from the NFL at the end of the season in what many critics alleged was a boycott.
"In this world of football, the quintessential American militaristic sport, there was this sense of how dare he," Sammons said.
Kaepernick was preceded by heavyweight champ Muhammad Ali, who objected to the Vietnam War and refused to fight in it. He was stripped of his title and lost five years of potential earnings after he was convicted of draft evasion.
U.S. track and field stars Tommie Smith and John Carlos endured death threats and damage to their long-term careers for raising their black-gloved fists in a Black power salute on the medal stand during the 1968 Summer Olympics.
Craig Hodges, a teammate of Michael Jordan's on the 1992 Chicago Bulls, was bounced out of the NBA shortly after he attended the team's post-title visit to the White House in a West African dashiki and delivered a letter to President George H.W. Bush, calling out his administration's treatment of people of color.
Today, more players across all sports are willing to take similar stands than there were during Hodges' playing days.
"When Major League Baseball cancels and there are very few Black American players in the league," Sammons said, "that's quite a statement about how the larger climate is changing and how masses of peoples and not just athletes are going to hold the team for standing up for racial justice."