What Viking said is my answer to your first part, Seamus. See Turkey, where the population took to the streets in support of the ever-more dictatorial Erdogan when the military of all things wanted to "save democracy", whatever one may think about that.
Nazi Germany, the GDR/DDR, North Korea and China may also beg to differ on the part where controlling a population is impossible. It doesn't work for the US elsewhere because the US are not willing / cannot afford to create an atmosphere of fear and repression. Even the ragtag ISIS "government" seems to have large areas under control using such fear tactics and public executions. You might even want to say this sort of system worked during the entire Middle Ages all over the world. Fear of death is a strong motivator, just see how muslims are often removed from planes because someone else fears them or how we spent billions on body scanners and other airport security. Both the Nazis and the DDR used that fear through the establishment of secret spy networks within the population. You do not need to control the thoughts, but if people don't dare talk about their thoughts to anyone, you basically prevent the formation of a sizeable resistance in most cases because people either don't dare to organize or get caught and ruthlessly executed before the movement is big and strong enough.
I'd say you need at the very least 20%, better 30% or more of the population in support of such a regime, but with the right incentives you can find such percentages in many countries.
If you assume for a minute that Trump would establish a similar system when elected and have around 50% of the voting population backing him up, where would the armed rebellion come from? The democratic gun control supporters? If those Trump supporters then supported the right of store owners to reject muslim customers for example, and then after two years, Trump and congress would pass a law banning muslims from entering shopping malls because it's just too dangerous to have them there and so on...perhaps they'd have to wear an armband with a crescent on it, too...
You think that could never happen? I would surely hope so, but I'm not so sure.
I mean I see your point and I like it, it's just once a sizeable majority uses the freedom to think what they want to think and express that others should be barred from those same freedoms that I think the freedom sort of defeats itself...
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