They didn’t know any better?

I might buy that if Steve King of Iowa or Ralph Northam of Virginia were middle school kids. But Mr. King, the Republican congressman stripped of his committee assignments when even Republicans could no longer tolerate his incendiary racist rhetoric, is no spring chicken. Nor is Mr. Northam, the Democratic governor; just about every other Democrat wants him to resign because of a past affinity for entertaining white people by donning blackface to mock black people.

Both men are veteran politicians who have taken oaths to serve all the people in their respective domains. Because to hold these offices is a privilege rather than entitlement, we demand better of public servants. Not perfection, mind you.

The House Republican leader, Rep. Kevin McCarthy, offered a clue about conduct expected when he said, regarding Mr. King: “Steve’s remarks are beneath the dignity of the party of Lincoln and the United States of America. His comments call into question whether he will treat all Americans equally, without regard for race or ethnicity.”

Mr. King is still trying to figure out what he did wrong. As his Iowa constituents greeted him like royalty just days after his colleagues took their action, the guy who likes white supremacists and Nazi sympathizers swore that he is misunderstood. “Not one soul has stood up and said Steve King has ever acted in a racist fashion, that he ever discriminated against anybody.”

Mr. Northam has many people trying to figure out why he keeps digging himself deeper into a hole as he tries to explain a yearbook photo from his medical school days in the 1980s. It shows one person in a Ku Klux Klan outfit and another in blackface, that practice of painting one’s face dark and exaggerating the lips to play to the most grotesque caricatures of blacks as buffoons.

Last Friday Mr. Northam took to the airwaves to apologize: “That photo and the racist and offensive attitude it represents does not reflect that person I am today or the way that I have conducted myself as a soldier, a doctor and a public servant.” But on Saturday he questioned whether he was in the photo at all. He said he had confused whatever the yearbook photo depicted with that time he darkened his skin and dressed like Michael Jackson in a dance contest in which he mimicked Jackson’s signature moonwalk.

Oh, my. His explanations get no better amid deafening howls for his resignation.

In an odd way, both men, and their bewildered defenders, prove why Black History Month — this month — is so necessary. I have long been ambivalent about a 28-day binge that permits a majority of the nation to think that regurgitating the same highlights once a year makes up for the inadequate integration of black history into American history, especially that offered in the public education system. I’m beginning to think that maybe Black History Month is needed to undo the miseducation of people who are not black, especially those like Mr. King and Mr. Northam who aspire to public office. The same may be said for months set aside to mark the contributions of women and various minorities. With missionary-like zeal, our goal can become less celebration and more education with outreach efforts aimed at grown folks who profess naivete.

It’s not that Mr. Northam has no place in public life. As Sen. Cory Booker, a New Jersey Democrat and a recently announced presidential candidate, said: “He should step down and start his road to redemption.” Once Mr. Northam gets his story straight and understands why blackface routines were always offensive but are now more likely to be called out publicly, he can become a credible emissary among his folks. He can turn the professed good intentions of his heart into something more tangible.

There’s an organization of mostly white folks that helps people like him do this. It’s called Showing Up for Racial Justice, SURJ for short, and its mission is “to undermine white support for white supremacy and to help build a racially just society.” Yes, Mr. Northam, there are chapters in Virginia. They’re here, too, in Maryland.

With Black History Month and the work of organizations like SURJ, ignorance is no excuse.

E.R. Shipp, a Pulitzer Prize winner for commentary, is the journalist in residence at Morgan State University's School of Global Journalism and Communication. Her column runs every other Wednesday. Email: ershipp2017@gmail.com.