My overall takeaways from the book were:
1. Class is correlated with income, but not identical.
2. Class is so ingrained in so many areas of our lives that it's almost impossible to change. You might as well just be comfortable with the class level you grew up in, because you'll probably always be there.
3. A big reason for #2: caring about your class in the first place is middle class. The more you care about where you fall in the class hierarchy, the more middle and upper-middle class you are. Lower class folks don't really care (and may even take a certain amount of "pride" in being lower / working class), and upper class people have nothing to prove to anyone.
But the book goes into excruciating detail about the way people dress, speak, decorate their homes, what jobs they have, cars they drive, etc, etc.
<< I should be largely invisible to the enforcer class.
The genie is out of the bottle. My health suffers if I think and express myself like you just did, although very eloquently. My roots are academic but my current state is prole. (ever read Fussell's Class?"  It is WONDERFUL!)
<< far more threatening to me than individual criminals.
I disagree. If you ever lose a relative to a gun or a drunk or cocaine, then storing a googol of data on me is never as threatening.
<< Any tool that can be used for legitimate police work can also be used for political oppression.
Maybe because I am political only one day of the year (or 2, depending), the day I vote, I do not feel oppressed.
data gathering is largely the problem there--so we address it through round about means.
According to Paul Fussell's Class: A Guide Through the American Status System, aversion to profanity is a middle class thing. The upper class do not use euphemisms for profanity or obscenity. Fussell wrote that Jilly Cooper reported "I once overheard my son regaling his friends: 'Mummy says pardon is a much worse word than fuck.'"
I doubt that many members of the upper class (see Fussell's book for a definition of upper class, it is roughly the tastes of "old money" but not dependent upon actual wealth) read Hacker News. It is likely that those who do not object to obscenities such as the word "fuck" are more socially liberal freethinkers who dislike formality. Those who do object are likely to be members of the middle class who believe (foolishly) that in censoring profanities and vulgarities, they are emulating the upper class. The phenomenon of "professionalism" is also a product of the middle class — to the upper class, selling things for a living is distasteful and déclassé. "Professional" language is usually very timid and full of circumlocutions as the primary goal is to not say anything that anyone may find offensive.
The upper classes would never get on their hands and knees and pound nails, because they feel that it is beneath them. The uppers are content with who they are, and don't give a damn what the lower classes think. But they are also uninterested in new ideas and would not be curious about your profession.
The rich people that you work for are likely to be upper middle class. They are likely to have earned their wealth by working hard, so they can relate to the hard work you do, even if their work was "white collar" instead of "blue collar".
The "middle class" that you describe seem to be Fussell's "middle" or "high proletarian". They are near enough to your class that they are bitter to you because they feel threatened by you, or because they think that their snobbery makes them better than you (it doesn't — usually this is the mark of a person with low self confidence). They might also not be there when you work, because are also at work.
I doubt that many members of the upper class (see Fussell's book for a definition of upper class, it is roughly the tastes of "old money" but not dependent upon actual wealth) read Hacker News. It is likely that those who do not object to obscenities such as the word "fuck" are more socially liberal freethinkers who dislike formality. Those who do object are likely to be members of the middle class who believe (foolishly) that in censoring profanities and vulgarities, they are emulating the upper class.
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