This clearly isn’t true, as the US has a per capita prison population four to five times that of China & Singapore! We jail far, far more people than they do.
I'm not even saying the solution is more/harsher policing. I'm saying it is a solution that seemingly works.
Overall, Singapore and China are significantly more willing to sacrifice freedom in exchange for security. There is more surveillance and no trial by jury, for example.
Qualified immunity was made up the United States Supreme Court in the 1960s. It is a buzzword.