That’s because, after WWII, you could do basically any job in the US and afford things we typically associate with the middle class, e.g. a modest home in a decent neighborhood. So everyone really was middle class.
People who work factory jobs aren’t “working class”? Who is working class then? To be honest, it sounds like your definition of working class is the definition that’s being stretched.
Upper / middle / lower class is about wealth. In a society with little income inequality, the middle class can become quite large. “Working class” is a class related to a type of work. In most places, the jobs that make up the working class are low paying, so the working class is also lower class. But this didn’t use to be the case in the US.
> The modern usage of the term "middle-class", however, dates to the 1913 UK Registrar-General's report, in which the statistician T.H.C. Stevenson identified the middle class as those falling between the upper-class and the working-class.
"Middle" literally stands for "between" working-class and upper-class. What do you think it's in the middle of?
You can also see https://en.wikipedia.org/wiki/American_middle_class#Academic... for a comparison of different contemporary models of the American middle-class specifically (all of which place the middle class in the middle of working-class and some other class, obviously).
