“ The smart way to keep people passive and obedient is to strictly limit the spectrum of acceptable opinion, but allow very lively debate within that spectrum. „
This has been a feature of American society as long as there has been an America. It was noted by Alexis de Tocqueville in 1835. There were strict bounds on what people could discuss, though within those bounds they could say what they liked. As opposed to, for example, English society, which traditionally was more accepting of the eccentric (upperclass) oddball.