you are always being watched.
I spent some time in Taiwan, Not Mainland.
The locals claimed that after dark one of every three people you passed, was a government informant.
Walked and took cabs everywhere, never a hint of a problem.
I always carried a card with my address in English and Chinese, in case I became lost, the people were very nice.
The people in the mainland are very nice and they like Americans. They have a massive police and military presence in the big cities, I believe it’s to show the locals who is in charge.