The Atlantic ran a curious article last week. Under the headline “Why Americans All Believe They Are Middle Class”, Anat Shenker-Osorio argues that Americans are encouraged by politicians, the media, and even colloquial language to believe that they belong to the middle class, when in fact they do not. Shenker-Osorio observes:

The puzzle is why so many who do not fit the category (as median family income reported as just above $50,000 defines it) believe they do. Why does the description “middle-class nation” continue to feel appropriate, desirable, or both?

There’s not much of a puzzle here. According to a Pew poll that Shenker-Osorio cites in the piece, Americans don’t all think they’re middle class. On the contrary, they’re pretty good judges of where they belong in the class structure, at least as defined by the distribution of income.

In 2012, the poll showed 32 percent of American identifying as lower class or lower-middle class, 49 percent of Americans identifying as middle class, 15 percent of Americans identifying a upper-middle class, and 2 percent of Americans identifying as upper class. That correlates reasonably well with the 25 percent of American household with incomes of less than $25,000 a year, the 50 percent who earn between $25,000 and about $90,000 a year, the 20 percent who earn between $90,000 and $180,000, and the 5 percent who earn more than that.

The similarities are particularly striking when it comes to the top tier. The top 2 percent of American households have incomes of more than $450,000. That seems like a plausible cutoff for the 2 percent of Americans who call themselves “upper class”.

Regional variations are extremely important in understanding differences at the margins. Well-paid professionals are clustered in cities like New York and Washington. They tend to call themselves middle class or upper-middle class because taxes and high prices, especially for housing, constrain their standard of living. The reason is not that they’re trying to keep up with the Kardashians. In low-cost areas, on the other hand, it isn’t necessarily crazy to consider oneself middle class on a household income of, say, $30,000.

Moreover, class is about more than income. As the great sociologist Robert Nisbet observed, the concept of class developed to make sense of Victorian Britain. It referred partly to differences of wealth and economic activity: businessmen were middle class no matter how rich they were. But it also indicated different mores, speech, and even physical characteristics. When Britain imposed military conscription during the First World War, it discovered that working class recruits were significantly shorter than soldiers from the upper class.

Charles Murray and others have argued the United States is moving toward a similarly visible class system. But it’s still not easy to tell at glance (or a listen) to which class Americans belong. Most look and sound like they belong somewhere in the middle. That’s the historically consistent and still distinctively American phenomenon that the Pew poll reflects.

So it’s reasonable to see the U.S. as a middle-class society, even though far from all Americans identify as middle class. The question is whether it will remain one. The Pew numbers show the number of Americans who identify as middle class declining from 53 percent in 2008 to 49 percent in 2012. Far from indicating that Americans are victims of false consciousness, that figure suggests that the norms and expectations that defined American social reality in the 20th century are eroding fast.