One of the contradictions of American society is that although race is central to the nation's history—a fact few deny—Americans often seem to struggle to see the ways that historical legacy continues to influence life today. (My colleague Ta-Nehisi Coates noted this tendency this week in a piece on comments Charles Barkley made about black criminality.)

Perhaps the problem is the lack of a comparative experience: If all you know is American society, you can't pick out the anomalies. That's why it's helpful to hear the voices of people like Chimamanda Ngozi Adichie. The novelist is the author of Americanah, and she may be best known to a broad audience through a sample of her TED Talk on the importance of feminism included on Beyoncé's "Flawless." Adichie was born in Nigeria but splits her time between there and the United States—"Home is where my best shoes are," she has said.

Many Americans seem to retain a vision of Africa as "the Dark Continent." Instead of the same base racism tropes of the past, there's a more nuanced, subtle one—the idea that Africa is a monolithic place, underdeveloped, perhaps disease-ridden, lacking in agency. Yet arriving in the United States, Adichie told Michele Norris at the Washington Ideas Forum Thursday, she was appalled by how, well, backward the country seemed in some ways.

"When I came to the U.S. I found myself taking on a new identity, or rather I found a new identity thrust on me," Adichie said. "I became black. I hadn’t thought of myself as black." In Nigeria, she noted, social divisions are about ethnicity and religion, not skin color.

"I’m very happily black. I don’t have a problem with having skin the color of chocolate," she said. "But ... I came to realize that in this country that meant something, it came with baggage. The idea of black achievement was a remarkable thing, whereas in Nigeria it wasn’t."

Her initial reaction was to separate herself from African Americans, to draw a line between herself as an African and black Americans. When one called her "sister" she objected—they weren't sisters. It was only after diving into American history that she got over that skittishness.

"It was a conscious effort," she said. "It's easy to internalize mainstream ideas. It’s easy to think the ghettos are full of black people because they’re lazy and like to live in ghettos."

Her critiques of American society haven't always been well-received by Americans, Adichie said. American writers have defensively asked why she didn't address racism in Nigeria.

"It's not what the book is about!" she laughed. "I don’t believe in provoking just for the sake of provoking," but occasionally only discomfort can jumpstart a conversation.

Coverage of the Ebola epidemic has provided more fuel for Adichie's critiques, she said. On the one hand, it's shown her that the U.S. isn't a great deal more competent than any other country: "Watching the fumbling and mumbling has made me realize that not dealing well with this sort of thing is not the exclusive preserve of Nigerians, which has been a nice thing to learn."

But the way the press has covered it has been frustrating, a good example of the way Americans see Africa monolithically and don't understand or perhaps simply can't be bothered to understand the differences between different countries. "And I don’t mean fringe reporting," Adichie added. "I mean the ostensibly responsible press."

Adichie was in Nigeria when the disease was there, though it has since been declared Ebola-free. But it feels to her as though Nigeria has been deprived of that victory. "It's been attributed to everything but Nigerian action," whether that's CDC intervention or something else. "It feeds into the same old narrative of 'Africa is a place with no agency.' If anything good happens, it has to be about someone else."

Disease is, after all, a great leveler—viruses know no borders. But neither, it's important to remember, does the scourge of racism.