Hallo,
Acquiring Citizenship in US after 5 years of stay is not straight forward as you mentioned, at the most legal immigrants or potential immigrants with H1B/L1 visa holders have to first acquire, Green Card so called PR. Queue, that means waiting time is in years( some times decade) years based on country of birth. Only then one can apply for Citizenship after completion of stay of 5 years after acquiring Greencard. So it is not so cheap as these SDP/FDP/Greens have contracted to sell Germany to illegal migrants. Australia, Canda and USA takes cream layer of educated migrants from 3rd world countires, Germany takes in contrary, one who stress the social system.
It is obvious, what is happening in France, UK and Sweden due to their liberal Citizenship after 5 years stay, soon native Europeans have to seek for refugges in Mars in future, Europe become unlivable.
My opinion is 5 years ok, but 3 years with whatever measures, seems to be nonsense.