perfidy

Correct. The masses never got behind a global class war/revolution, or even in Imperial Russia. The Marxist prophecy never materialized. It didn't happen. Marx prophesied that the vanguard of the proletariat would initiate the class war and the rest of the proletariat would quickly follow. That did not occur. As far as I know, Jesus hasn't shown up again either. The Marxist prophecy will never happen because the world changed significantly after the mid-nineteenth century, and no, the workers never got behind it, nor will they ever.

The United States does have a class system, but as you indicated it is what the sociologists call an open stratification system. Well, even a broken clock is right twice a day so the sociology folks were bound to get something right thanks to law of averages. But still. Just because mobility is possible between classes it does not mean the classes do not exist. They are fluid, but they are there. Upward and downward mobility is possible, people can go from working to middle to upper and back down to working again. But at every step, there is a step. A permanent social structure is called a caste system. That's when the social ladder is entirely hereditary and is also known as a closed stratification system where no mobility is possible.

In the United States, classes are based entirely upon wealth and education. There is no hereditary aristocracy, but that doesn't mean it doesn't have a class structure. See, in Britain and much of Europe, with the industrial revolution, the hereditary aristocracy constituted the upper class, non-titled wealthy and well-to-do educated professionals, shopkeepers, etc. constituted the middle, urban and rural workers the working class. With the industrial revolution, Britain and Europe moved from a caste to a class social structure when mobility became possible between the working and middle classes. Not guaranteed, no, but possible. Hell, some people in the middle class even bought themselves a title to move into the aristocracy. Thus, it is mobility that distinguishes a class from a caste structure, and the United States holds the possiblity fo mobility, be it upward or downward. My terminology in describing the United States as a nation with a class structure was correct.