@richpuchalsky
I agree with the superstructural analysis on how policy inconsistency with ideology enabled oppositional propaganda, and that the collapse of the USSR removed geopolitical counterhegemonic pressure, but I'm not sure that it's fully explanatory. It does somewhat deny the impact (and therefore prescriptively, agency) of civil rights, anti-war and union campaigners in mobilising to exert political pressures, or investigative reporters delivering uncomfortable truths that move the needle significantly, like Watergate.
Also, in the period immediately after the fall of the USSR, there were substantial pressures arising from the anti-capitalist, climate change and anti-globalisation movements, as well as a new ideology of "self-determination" deployed to support the economic liberalisation of former communist states, to which some pantomime of consistency had to attach. The rupture of 9/11 (imo) was what enabled the transition in ideology to ethnonationalist supremacy (though America First was yet to slouch to birth), the end of rhetorical fundamental rights based protection (selectively, under exigent circumstances designed to loosen via the Patriot Act and the creation of DHS) and the War on Terror, conducted in a deeply socially repressive psychological climate where dissent was traitorous in principle.
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