Peter Turchin has an interesting piece in Aeon Magazine (rapidly becoming a very good website) on cycles of inequality in history and at present.
How, though, can we account for the much more broadly inclusive policies of the Great Compression era? And what caused the reversal that ended the Gilded Age and ushered in the Great Compression? Or the second switch, which took place around 1980?
History provides another clue. Unequal societies generally turn a corner once they have passed through a long spell of political instability. Governing elites tire of incessant violence and disorder. They realise that they need to suppress their internal rivalries, and switch to a more co-operative way of governing, if they are to have any hope of preserving the social order. We see this shift in the social mood repeatedly throughout history — towards the end of the Roman civil wars (first century BC), following the English Wars of the Roses (1455-85), and after the Fronde (1648-53), the final great outbreak of violence that had been convulsing France since the Wars of Religion began in the late 16th century. Put simply, it is fear of revolution that restores equality. And my analysis of US history in a forthcoming book suggests that this is precisely what happened in the US around 1920.
In 1921 and 1924, Congress passed legislation that effectively shut down immigration into the US. Although much of the motivation behind these laws was to exclude ‘dangerous aliens’ such as Italian anarchists and Eastern European socialists, the broader effect was to reduce the labour surplus. Worker wages grew rapidly. At around the same time, federal income tax came in and the rate at which top incomes were taxed began to increase. Somewhat later, provoked by the Great Depression, other laws legalised collective bargaining through unions, introduced a minimum wage, and established Social Security.
The lesson for today: do something similar which would presumably mean restricting immigration, taxing the wealthiest, and protecting the less well-off. Alas, this package is not currently within the Overton Window.