Toronto Raptors coach Dwane Casey was born into the Jim Crow South. For most of his childhood, he lived with his grandparents in rural Kentucky. His grandfather cleaned a local hotel at night but wasn't allowed to eat there during the day.

Casey, 60, remembers Klan rallies rolling through the centre of town. He remembers white parents standing at the door of his desegregated grade school, screaming at black students. He remembers all the worst things about the most divisive period in recent American history.

Read also: By sparking national anthem debate, Trump divides and conquers

Story continues below advertisement

"I came through the sixties and seventies," Casey said. "And it's eerily getting back to that."

He was speaking as part of the Raptors' annual Media Day that took place on Monday. It's usually a very light affair – a few laughs, a few new arrivals, a lot of, "I'm in the best shape of my life" talk.

U.S. President Donald Trump changed the mood this year. His splenetic outbursts over the weekend have galvanized professional sports – or at least the faction of it that is his target.

It has been fascinating watching white football players trying desperately not to upset anyone – neither their black teammates nor their white fans.

Though dozens and dozens of NFLers knelt on Sunday during the national anthem, precious few of them were white. Green Bay Packers quarterback Aaron Rodgers did manage to kneel on Instagram but not on the field. New England Patriots quarterback Tom Brady replied to Rodgers' photo with an arm-flexing emoji . It felt more like marketing than solidarity.

Thanks to the Pittsburgh Penguins' curious decision to announce, unprompted, that they will be going on a White House visit, the NHL has been forced to confront issues its players seem ill-prepared to address.

While the Raptors were speaking out forcefully and with one voice, across town poor Auston Matthews, all of 20 years of age, was in the Toronto Maple Leafs camp tiptoeing through a rhetorical minefield.

Story continues below advertisement

"I'm not really a huge politics guy, but obviously there's some stuff going on that's hard to miss and, um, yeah," Matthews said. "To me, I don't know if kneeling, sitting, stretching is really something I'd look into doing. To me, it's like a dishonour to the men and women who fight for that flag."

Though it took him a while to get there, Matthews said he would visit the White House. Hockey is thus far also speaking with one voice on this issue and I don't think their "good company man" approach is doing them any favours.

It is a bit of an unfair ask in Matthews's case. There is no circumstance under which the Leafs would be invited to a photo op with the U.S. President. But, overnight, this question has become the loyalty test of pro sports: Would you shake Donald Trump's hand? Whose side are you on?

As a Canadian franchise, the Raptors would probably not get that call either, but club president Masai Ujiri wanted people to know where he stood regardless.

"We get to go to two White Houses [in Washington and Ottawa], right?" Ujiri said. "I think we'll be fine with Trudeau."

Many people have been put through this purity trial over the past couple of days and there have been few surprises. Until Casey was asked.

Story continues below advertisement

"I'd love to go to the White House," he said. "That would be the players' decision, but myself personally, I'd like to go look the guy in the eye and let him see that I'm not the perception that he has. You can do things by example … that may be a way of changing."

What would you say to Trump?

"I would just say that I've been through the sixties and the seventies and maybe he didn't mean to put a lens on the football players, but the majority of them are African-Americans," Casey said. "The perception is he said: You don't have a right [to protest], sit down, fire them. It looks like you're talking down to the African-American football player. That's what I would have a conversation with him about, man to man."

There are many remarkable things about what's happened over the past few days and one of them is the tone: As Trump goes low, the athletes stay high.

The worst any Raptor would say of their new antagonist-in-chief was DeMar DeRozan calling him "our so-called leader."

Casey was cutting in a more subtle way. While speaking of Trump, he did not once call him by name. Small courtesies matter to Dwane Casey and when he does not offer them, it says more than any insult.

Story continues below advertisement

We're still in the early stages of wherever this is headed, but the careful civility can't last. All of the American wounds that are usually papered over in pro sport by money, pomp and PR specialists are being reopened.

Eventually, everyone involved will have to address them. Choosing not to is its own sort of pronouncement.

We talk a lot about turning points in sport, but this may actually be one – a crucible that forces all athletes to reckon with the world away from the court, the rink and the field. Maybe for the first time in quite a while.

Casey speaks with more authority than most on the subject because he has seen with his own eyes where division leads and has come through it with a spirit so generous that it is humbling to be around.

"Sports should be the glue that brings society together," he said. "That's what I use it for."

You can get so far down in the minutiae of these issues that, eventually, you're arguing semiotics – what does kneeling mean? Who is this all directed at? Is it the office or the flag or the man or the military or the … you can whittle this idea down to functional meaninglessness.

Story continues below advertisement

That's the real arc of history – arguing around contentious issues and doing so endlessly. This great shaking in the sports world may just be more of that, to no real end.

But there is no debating who has the moral high ground in this particular fight. People are being asked to decide between Donald Trump's vision of the world and Dwane Casey's.

When you think of it like that, the choice gets very simple.