Donald Trump is now hip-hop’s biggest heel. He used to be one of its biggest heroes.

Eminem’s four-minute evisceration of President Donald Trump, which debuted Tuesday night at the BET Hip Hop Awards, is the latest in a series of diss tracks aimed at the often-reviled commander and chief.

What the a cappella bars lacked in melody, they made up for in lyrical and political potency.

They also rounded out a Trump hip-hop about-face two-plus years in the making.

In 2015, Em, like dozens of his peers in the hip-hop world, was dropping Trump’s name in freestyle sessions like the one he did on Sway in the Morning.

“I fuck worse than Donald Trump on Lexapro, in Mexico, across from a Texaco at McDonald’s drunk,” the Detroit rapper quipped.

The same year, Mac Miller and Rae Sremmurd were evoking Trump in their own odes to his air of bombast — his gilded buildings, his misogynistic objectification of women and his propensity to verbally attack his critics are common hip-hop tropes.

Trump’s name, like Bill Gates’, once epitomized rap’s fixation with wealth and status. Today, for many like Eminem, born Marshall Mathers, Trump’s image represents racism and oppression.

Prior to his White House win, the former Celebrity Apprentice star was mentioned in at least 67 rap songs, according to the Huffington Post.

And the love affair went both ways.

Trump hosted Uncle Luke at his South Beach bachelor pad back in the early 1990s. He befriended hip-hop legends like Russell Simmons.

He even praised Eminem during a 2004 interview with Playboy, while boasting of his own popularity in the hip-hop world.

“I think Eminem is fantastic, and most people think I wouldn’t like Eminem,” Trump said. “And did you know my name is in more black songs than any other name in hip-hop?

“Black entertainers love Donald Trump. Russell Simmons told me that. Russell said, ‘You’re in more hip-hop songs than any other person,’ like five of them lately. That’s a great honor for me.”

That was then and this is now.

Since running for president, Trump has inspired, perhaps, more hip-hop disses than any politician since Ronald Reagan.

YG and Nipsey Hustle’s not-so subtle 2016 campaign diatribe “FDT (Fuck Donald Trump)” is one of several Trump-related rap takedowns released since the president’s racially-divisive rhetoric split America into hyperpartisan pro-Trump, anti-Trump camps.

“I like white folks, but I don’t like you, All the n*ggas in the hood wanna fight you,” rhymed the Grammy-nominated Compton, California rapper. “Have a rally out in L.A., we gon’ fuck it up. Home of the Rodney King riot, we don’t give a fuck.”

New York’s Uncle Murda dissed Kanye West for his November Trump Tower photo op with the then-president-elect before calling for Trump’s death in the “Rap Up 2016.”

“Damn Ye, the people don’t trust you/ Bush don’t like black people, but you think Donald Trump do?” Murda rhymed. “Don’t meet with Donald Trump to talk about us, Ye/ You ain’t got the answers, just like you told Sway.”

Questionable morals aside, there’s nothing less hip-hop than racism. It’s a deal breaker.

The genre’s roots lie in giving marginalized groups a voice to speak out against societal ills like poverty and police brutality.

Trump’s tacit endorsement of police misconduct, his rhetoric about Mexican “rapists” and “criminals,” the adulation he’s received from white supremacists, are all about as un-hip-hop as it gets.

He’s become synonymous with everything old-school legends like KRS-One, Public Enemy and NWA built careers musing against.

Today, icons-in-the-making like Kendrick Lamar have taken the political rap torch and run with it. “Are we gonna keep talking about it or are we gonna take action?” Lamar said in an interview with Esquire published in August about not directly mentioning Trump on this album, DAMN.

Trump’s rapid descent on the culture’s proverbial shit list should come as no surprise.