There are 11 million Uighurs, and about a million in the camps. There are over 30 million blacks in the US, and under a million blacks in jail. (2.2 million is the total number of prisoners.)
The situation in Xinjiang is therefore much worse.
Most of the people concerned should not be locked up anyway—think of people who can’t afford to pay fines in the US, or people who pray in Xinjiang. It is extremely rare that a population is so poorly socialised that it is necessary to imprison over a tenth of the population. Perhaps they are in some strict sense “criminals”, but China can choose who to criminalise (as can the US), and it is clearly making unhelpful decisions.
The situation in Xinjiang is therefore much worse.
Most of the people concerned should not be locked up anyway—think of people who can’t afford to pay fines in the US, or people who pray in Xinjiang. It is extremely rare that a population is so poorly socialised that it is necessary to imprison over a tenth of the population. Perhaps they are in some strict sense “criminals”, but China can choose who to criminalise (as can the US), and it is clearly making unhelpful decisions.