As some Americans increasingly profess to believe in the notion of colorblindness, it's important to understand why Michael Sam came out to the world on Sunday by mentioning both his sexual orientation and his race. That's because he's not just a trailblazer for LGBT athletes in sports. He's also the successor to decades of changes in the evolution of Black masculinity.

Back in the 1970s, when male dancers on Soul Train sported colorful blousy shirts and blowout Afros, NBA stars like Wilt Chamberlain and Kareem Abdul Jabbar of the Lakers were still wearing tiny basketball shorts that today's ballers would find less than masculine. The world was different then. Few professional athletes had tattoos. Straight men rarely wore earrings.

By the time I became a high school and college athlete in the mid-1980s, things had already begun to change. Michael Jordan introduced longer basketball shorts to the NBA. Hip hop helped to popularize tattoos for men who weren't sailors. And straight men were beginning to wear earrings, as long as they observed the arbitrary decree that "left is right and right is wrong."

But as we reached the 1990s, the world seemed to be evolving faster than the Black community, or the nation at large, was willing to accept. Lakers star Magic Johnson retired from basketball after announcing his HIV status in 1991. Former New York Giants guard Roy Simmons came out as a Black gay man on The Phil Donahue Show in 1992. And tennis legend Arthur Ashe died of AIDS in 1993.

The AIDS epidemic pulled back the curtain on African-American sexuality, and yet the "coming out" process that started with black gay baseball player Glenn Burke in the 1970s would take another two decades after the 1990s to generate athletes like Wade Davis, Jason Collins, Kevin Grayson and now Michael Sam. By the time we would finally elect a Black president, he would challenge our social conservatism and lead us to realize our old-fashioned assumptions about African-American athletes and Black masculinity were socially constructed myths that trapped the athletes as much as the society around them.

That's why it was significant that Michael Sam came out Sunday, in the same weekend when Eric Holder, the nation's first Black attorney general, announced he was expanding benefits for same-sex couples. It was also the same week in which President Obama announced the nomination of Darrin Gayles to be the nation's first black gay federal judge. And it was the same winter in which two Black gay male couples were married on live television at the Grammy Awards by Queen Latifah.

This is the environment in which Michael Sam told the world his truth. "I'm a college graduate. I'm African-American, and I'm gay," said the 24-year-old University of Missouri senior, thus launching himself on a path to become the first openly gay NFL player.

Among the few openly negative reactions, an NFL insider told Sports Illustrated the league wasn't ready for an out gay player. "In the coming decade or two, it's going to be acceptable," the source said, "but at this point in time it's still a man's-man game."

I hope that person wasn't Black, partly for his backward and anachronistic interpretation of manhood, but mostly because his suggestion that a whole generation of athletes should wait a decade or two to be true to themselves stems from what Martin Luther King, Jr. once called a "tragic misconception of time." It's based on "the strangely irrational notion that there is something in the very flow of time that will inevitably cure all ills," as Dr. King said. Actually, he told us, "time itself is neutral; it can be used either destructively or constructively."

In fact, the anonymity of the quoted source to Sports Illustrated provided the clearest indication of the success of earlier activists who had used their time to create change instead of waiting for the perfect moment for society to change itself.

That change could be seen among the expressions of support that poured in Sunday evening, including from NFL wide receiver Chad Johnson, who took to Twitter to praise Sam's "courage," and NFL legend Deion Sanders, who acknowledged that Sam wouldn't be the first gay player in the league, just the first to come out while playing.

The NFL expressed its official position in a statement admiring Michael Sam's courage and offering to support him in the league. "Any player with ability and determination can succeed in the NFL," the statement said. That remains to be seen.

Nearly 70 years after Brooklyn Dodgers general manager Branch Rickey offered a contract for Jackie Robinson to break the color barrier in baseball, the NFL may need a modern-day Rickey to see beyond Michael Sam's sexual orientation and recognize the potential in drafting the SEC's defensive player of the year. That's why it was encouraging Sunday night that New York Giants co-owner Steve Tisch praised Michael Sam as a "gifted athlete and a courageous man."

Similar to Jackie Robinson, Michael Sam has been preparing for the scrutiny. As sports commentators spent Sunday debating 19-year-old Marcus Smart's suspension for shoving an obnoxious fan at a weekend game, Michael Sam had already been media-trained to answer ESPN's question about a hypothetical taunting he might receive. "I don't let stuff like that distract me," he said.

He's going to need that cool head as he makes the transition to the NFL and pries open the closet door that has kept so many in the shadows. It won't be easy, and for some it won't be convenient, but progress never is.

Keith Boykin is a New York Times best-selling author and former White House aide to President Clinton. He attended Harvard Law School with President Barack Obama and currently serves as a TV political commentator. He writes commentary for BET.com each week.

The opinions expressed here do not necessarily reflect those of BET Networks.

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