1968 was an explosive year in the U.S.
The year remains etched deep into the country's history as one that changed the course of the nation, politically and socially.
1968 was the year Dr. Martin Luther King was assassinated after leading the civil rights movement. 1968 was the year the anti-Vietnam War sentiment was in full motion.
And 1968 was the year Olympic sprinters, John Carlos and Tommie Smith, stood on a medal podium during the Summer Games in Mexico City, bowed their heads and raised black-gloved fists during the playing of the national anthem as their way of protesting social inequalities in the country.
The athletes, who are both National Track and Field Hall of Famers, were kicked out of Olympic Village and were suspended from the U.S. team, according to Time.com. Neither men have ever apologized for their actions and the moment is still considered one of the most powerful displays of defiance in sports history.
So what does 1968 have to do with the year 2016?
San Francisco 49er's quarterback Colin Kaepernick caused an uproar after choosing not to stand for the national anthem during a preseason game Friday night in Santa Clara.
Kaepernick told NFL Media that he refused to “stand up to show pride in a flag for a country that oppresses Black people and people of color.”
The powerful moment Carlos and Smith held in 1968, marked the moment the athlete activist was born. Kaepernick is just the latest athlete to join the movement.
The sixties brought forward other legendary names, such as Muhammad Ali. Considered to the greatest heavyweight boxer who ever lived, Ali was also one of the most famous social activists who ever lived. Ali was born Cassius Clay, until he converted to Islam and changed his name to what the world came to call him. He often spoke out against poverty and social inequality, and even refused to fight in the Vietnam War.
As a result, Ali was stripped of his heavyweight crown and had to go through the Supreme Court for his actions. Eventually, his case was overturned but not until after he had made some major noise.
Billie Jean King also made history during the athlete activist 'golden era' of the late 1960s and '70s. The tennis pro fought for equal pay for women athletes and pushed for women's sports to be covered in media. King was an early advocate for LGBT rights. She came out as gay in 1981 and lost all her endorsements over the controversial revelation.
This 'golden era' produced many more athlete activists, most of who faced harsh backlash during a tulmultuous time in the nation.There have been few athletes that have made history books since the golden age of political activism in sports, but why?
A big reason: money.
Today, athletes tread much different waters. In past generations, social activist athletes such as Ali, Carlos and Smith didn't have to represent a structured brand. Many athletes today perform under leagues that operate like corporations, according to thinkprogess.org. There are tickets and merchandise to sell, multi-million dollar endorsements to land. New factors like television and free agencies changed the sports business model and allowed for much larger salaries. Athletes are reluctant to rock the boat. Stirring controversy could mean risking a livelihood most are unable to have outside of big brand teams.
Athletes also don't want to be labeled as a distraction to the team. Distracting from a team or sport is highly frowned upon in athletics, according to Think Progress.
For example, Kaepernick's protest happened during the team's preseason opener. In other words, during his on-the-clock hours as a professional athlete for a team sport.
Choosing not to stand during the National Anthem at Friday's game not only puts the media spotlight on Kaepernick, his team also has to speak to the controversial protest when asked during unrelated interviews.
There is the exception of being a well-known, established athlete, such as Lebron James.
In 2012, James tweeted a photo of the entire Miami Heat team wearing hoodies and standing with their heads bowed in a tribute to Trayvon Martin, an unarmed, black Florida teenager who was shot to death after being profiled by a neighborhood crime-watch volunteer.
In 2014, Derrick Rose-- who at the time played for the Chicago Bulls-- wore a T-shirt before a game that read, “I Can’t Breathe,” the words repeated by Eric Garner as he died while in a chokehold during a confrontation with Staten Island police. James and other NBA players followed Rose's lead shortly after, wearing the same T-shirts.
James and Rose make a combined salary of nearly $264 million dollars and are both in the top 30 most-paid players in the NBA. Either of them can afford losing a few million dollars in endorsements for a cause if they wanted to stand up for something they believe in.
So, Kaepernick might be making all the headlines at the moment, but he's certainly not the first to do so.
ABC10's Bryan May offered his take on the infamous Kaepernick protest and how it's distinct from athlete activists in history:
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