The reality is, obviously, that they do not want to arrest Western visitors. In fact they want Western visitors to get the best opinion of the country possible and go home telling every one how great China is.

I fully agree: China is not a democratic country, and there is no independent judiciary, and crossing the wrong people while there is a bad idea (is there a country where it's a good idea, though?)

But let's not claim that it is dangerous to visit or even to move to for work. It is very safe.