Credit R. Wallace “Wally” Hudson, chairman of the Mecklenburg County (Va.) Republican Committee, with demonstrating how new social media platforms can broadcast ancient hates.

The Post [and other media] reported this week that the county GOP’s Facebook page had displayed for months photos portraying President Obama as a witch doctor, a caveman and a drug dealer.

Ah, life in post-racial America.

Virginia’s Republican Party chairman, Pat Mullins, ordered the offensive photos be taken down. But Hudson, who acknowledged posting most of the images, stood his ground, saying he didn’t see what all the fuss was about. “We know our regular readers, who are good conservatives,” he told The Post on Tuesday. “They’re gonna get a kick out of it.”

Who better than Ol’ Wally to know?

Sadly, the Mecklenburg GOP’s disgusting images — which have since been removed — are not an isolated case of ugliness.

Baylor University assistant professor Mia Moody did a study of social media stereotyping of Barack and Michelle Obama; her findings appeared in the journal New Media & Culture.

Moody researched hundreds of Facebook groups and pages. She found numerous examples of the president and the first lady being targeted with racist and sexist rhetoric that, not surprisingly, also indirectly spread hatred toward women and blacks.

She uncovered pages with titles such as “I don’t discriminate, I hate the white part of Obama too,” and “Yes, I hate Obama because he’s black.”

She also found groups that claimed to be motivated only by politics but whose sites still led to racist rhetoric.

The mission statement for one such group stated: “No! I don’t hate blacks! I just think Barack Obama is a terrible president.” Its page posed the question: “Don’t you just hate it when people call you racist because you hate Barack Obama? Do they ever consider that Barack Obama may just be a [expletive] president?”

Moody observed that, while the group professed to dislike Obama not because of his race, most comments on the page attacked the president “personally with racial slurs.” Just one example: “Obama needs to step down and go back to Africa with the rest of the coons!! He’s nothing but a jigaboo and spear chucker!!”

That site, Moody wrote, was archived and later removed from Facebook.