If Michael Bradley’s Instagram missive had been unexpected, the first few comments below it weren’t at all.

“Please stick to what you know, and let the professionals do the hard work,” wrote jsquared1013. “I’m not out there critiquing your performance at WC2014, because I don’t know enough about playing midfield to know what I’m talking about.”

Jsquared1013 did not elaborate on what made him more qualified to talk about politics than the U.S. national team and Toronto FC captain. Nor did he explain what about his experience allowed him to call out the 29-year-old midfielder on politics, although he did claim a military background, even though that isn’t terribly germane to the matter.

Predictably, there were more calls for Bradley to “stick to sports” – a catch-all admonishment of professional athletes, and others even peripherally involved in pro sports, not to wade into political subjects.

But Bradley, who had to that point rarely taken strong public stances on anything outside of soccer – and not all that often about things in the game either – had decided to speak out about the election of Donald Trump as president and his proposed travel ban on several Muslim-majority nations.

“While I understand the need for safety, the values and ideals of our country should never be sacrificed,” Bradley wrote in late January.

“When Trump was elected,” Bradley continued, “I only hoped that the President Trump would be different than the campaigner Trump. That the xenophobic, misogynistic and narcissistic rhetoric would be replaced by a more humble and measured approach to leading our country. I was wrong. And the Muslim ban is just the latest example of someone who couldn’t be more out of touch with our country and the right way to move forward.”

While there’s a rich history of social activism among athletes, most have long been cagey about this sort of stuff. Michael Jordan famously said “Republicans buy sneakers, too,” when asked why he didn’t speak up about politics, although he’s become more outspoken in recent years. The urge not to alienate any fans is understandable. Athletes work in the public eye and are expected by many to be neutral automatons that only think about sports. They’re in the entertainment industry, offering escapism. Fans mostly prefer for day-to-day political squabbles not to pollute their sports.

But wading into the murky waters of public opinion has become more fashionable. Most notably, NFL quarterback Colin Kaepernick has protested racism, while four NBA superstars used last year’s ESPYs to call for further social engagement from athletes and WNBA players wore Black Lives Matter t-shirts during warmups last season.

NBA coaches Gregg Popovich and Steve Kerr have become vocal critics of the Trump administration as well. And while U.S. national team manager Bruce Arena wouldn’t opine on the subject when asked, a slew of American soccer players has begun chiming in too.

Because Bradley, while applauded by many for his honesty and courage, is hardly alone.

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New York Red Bulls captain Sacha Kljestan regularly retweets news items that call out the hypocrisies of the new government and occasionally adds his own voice. That puts him on the other end of the political spectrum to his boss, Dietrich Mateschitz, the Red Bull founder who is a public Trump supporter and apparently has plans to create a kind of Austrian version of the right-wing Breitbart News website.

Philadelphia Union star Alejandro Bedoya was so offended by the aspersions President Trump cast on Sweden, that the midfielder, who spent parts of five seasons playing there, felt compelled to go on CNN to defend his former home.

Bradley, Kljestan and Bedoya all declined interview requests on this subject with Yahoo Sports, saying that they have nothing to add to their public statements. And their reluctance to provide insight into the thinking behind their tweets or Instagram posts – preferring for them to stand alone – is both reasonable and indicative of the delicate nature of mixing sports with politics.

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Veteran Major League Soccer midfielder Jeb Brovsky, who is currently out of contract after tearing his ACL in October, is glad to explain himself.

“I’ve always seen social media as an extension of self,” he said. “There’s nothing about me that I don’t want the public to know, that I’m hiding. A lot of people disagree with me, but I do believe that if you have that belief and that conviction, you have to be authentic about that and put it forward.”

Austin da Luz, a midfielder for North Carolina FC in the NASL, feels the same. “I think it’s important for any citizen to speak out about things they believe are important or are going to affect their daily lives – especially now,” he said. “I would never pretend to be an apolitical person.”

“The country that we live in, it’s important to engage on these subjects,” echoed Toronto FC goalkeeper Clint Irwin. “I don’t think my opinion should stick out more than anyone else’s. But there comes a point where the sheer number of people speaking out is important. A vast amount of us has become apathetic. As President Obama said, ‘We get the politicians we deserve.’ And if we don’t vote, and if we’re not engaged, this is what we get.”

Irwin, who studied political science and philosophy at Elon University, embraces the chance to engage on non-soccer subjects. As a regular for most of his four seasons and change in Major League Soccer, he interacts with the media quite a bit. But the questions seldom stray outside of soccer. “A lot of the questions aren’t going to be on this week’s fresh political fight,” he said. “That’s more what I would like to give my thoughts on sometimes.”

While Irwin doesn’t mind talking soccer, spitting out platitudes can become tiresome. “It gets kind of rote sometimes,” he said. That’s where Twitter comes in handy, as an alternative release.

But Irwin imposes something of an embargo on himself, because he wants to consider things before he tweets, rather than reacting to news immediately. “It’s hard to sustain the outrage, at least for me,” he said. “It seems there’s this outrage loop where something comes out and people are angry about it and then new information comes out. I wait for things to play out and try not to be so reactionary all the time.”

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At its base, “stick to sports” is an odd thing to say to someone. We don’t tell plumbers to stick to plumbing, or accountants to accounting. If opinion was to be invalidated and suppressed because of the opinionator’s employment in an unrelated field, the world would be an awfully quiet place.

“I just think it’s silly,” said da Luz, who recently set up Playing for Pride, raising money with other male and female pro players in North Carolina for LGBTQ rights, which have come under assault in that state. “Unless I’m dribbling down the field and I stop to talk to the referee about gerrymandering or healthcare, I don’t really understand it. What I choose to speak about off of the field is totally my choice and nobody can take that right away from me.”

“When people say ‘stick to sports,’ all I really hear is that A, you don’t agree with me, and B, you’re not willing to engage with what I’m saying,” da Luz continued. “Which makes you the problem, not me. What I’m talking about outside the white lines, you have a choice about if you want to listen. I don’t really see that as a valid argument.”

Irwin argues that there’s no clear delineation between sports and politics any longer anyway, pointing out that the travel ban affected pro soccer players. “When you talk about stick to sports, well, things we’re talking about are affecting sports, affecting our lives,” he said. “It’s important that we stick up about it. We have a stake in this, in our country. We’re no different from any other citizen.”

Brovsky says politics is the subjection of discussion “quite a bit” in MLS locker rooms. Yet most shy away from it publicly. He’s an outlier in that he’s unbothered about brand-building and put off by artifice for the sake of being palatable to as broad a public as possible.

“My priorities are a little bit different, certainly, as I’ve gotten older,” Brovsky said. “When I first got into the league I shared that philosophy that a lot of athletes do – don’t ruffle feathers, you’re a rookie, just kind of tread water and don’t upset the establishment too much. That’s where I think a lot of athletes come at social media from. ‘One tweet, one message can ruin my entire career.’ But if you’re taking that hesitant an approach you’re not giving your authentic self.”

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Brovsky concedes that not being a major star means he doesn’t have quite as much to lose as others – unlike Jordan, he has no sneakers to sell. He has no portfolio of endorsements that could dump him. “I have to be honest and say I’m sure my attitude would change toward being so open about it,” he said.

Yet Brovsky and others believe that if you have a platform, you also have some responsibility to use it for what you believe is good. “We live in a world where we have a president who has openly attacked certain ethnic groups and alienated half of the country, instead of uniting it,” he said. “For me and a lot of American players, this social and political time that we’re living in kind of requires us to be more involved civically.”

Da Luz agreed. “The time for casual morality has passed,” he said. “We need more people in the driver’s seat, pushing things in a positive direction. The more people get involved and speak out, and the more conversations we’re able to have, the better off we’re going to be. No matter what side you come down on it – right now, I don’t think we’re in a great spot. And just telling people, ‘stick to sports; stay in your lane’ isn’t going to solve anything.”

Leander Schaerlaeckens is a Yahoo Sports soccer columnist. Follow him on Twitter @LeanderAlphabet.

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