@nidud, that's a dramatic graph! The anti-correlation of unions and income is so perfect one suspects fudging. Note, it comes from (presumably biased) "unionstats.com". Nevertheless I can believe it. Of course they want you to think unionization causes income equality. But to significant extent they're both caused by other factors. For instance, as you say, "the class struggle seems redundant when things are going well."
Note JJ's stats are about overall wealth not just income. Wealth is much more extreme, and much more important when you get into the upper 5 or 10%. Thus income going to top 10% is only 50% or so, while wealth is something like 84% (current USA).
The graph shows today is about the same as roaring 20's. But care must be taken comparing the eras. In 20's poor farmers throughout the bulk of the country could get by with more or less zero income, living off the land. Impossible today. The farther back you go the more important to keep this in mind. Inequality was huge in the age of Crassus but most of the Roman Empire had little need of money. Thus a case can be made that effective inequality in US today is worst in World history.
How does this compare, I wonder, to Europe during the same period? Of course the wars distort the data a lot. But can one claim a similar correlation between unions (a.k.a. socialism, even communism) and wealth inequality?
Bottom line: I'm not entirely convinced but yours is a very relevant point.
@JJ, yes oil crisis was a major factor, caused by the Yom Kippur war. Not surprising that a European would forget the other crisis: Watergate. Viewed from here, it looks just as important. I wonder if there are underlying factors linking them.
It was 1976 when I first noticed that Wall St. was beginning to steal all the money. When I started working, fellow students who just weren't good enough to cut it as "real" mathematicians went to Wall St as a consolation prize. My starting salary was about 1/3 higher. Later the starting salaries of new Wall Streeters was equal to mine, after 5 years of big raises! Couple decades later they were starting around a million. Non-financial mathematicians were no longer in the running. Wall St has never stopped that incredible increase. Milliken stole half a billion; decade later, hedge fund managers were stealing 5 billion at a shot; Now Zuckerberg hit 55 billion. 20-30 years will see the first trillionaires.
@anunitu, oil and energy are very important. But in the big scheme of things they are, I believe, red herrings. Notice that when oil prices are up, Wall St steals lots of money. When they're down, Wall St steals lots of money. When people get angry and pass new laws restricting Wall St activity, Wall St steals a lot of money. Do you see a pattern? They've stolen, directly, at least 10 trillion in these decades. Indirectly, another 20 or so I guess.
