Be careful what you're seeking to compare; with 11M Uyghurs and 1M of them in re-education camps, China has far more of a percentage of the underclass imprisoned (9%) than in the U.S. (with 1.35% of the black population imprisoned). This isn't to defend the prison practices of the U.S., which are still generally indefensible, but some heart can be taken in that the number of U.S. imprisoned (of all races, but especially black prisoners) has fallen year-over-year for more than a decade, whereas China's re-education camps are still growing.
Interesting. My first thought was that your number was too low, but searching a little it seems you are right, with a couple caveats. The first caveat is that the number for black males is about twice that of the black population as a whole (ie, black females are rarely imprisoned).
The second caveat, which is not one I've seen widely reported, is that the percentage of black males currently imprisoned has dropped sharply over recent years, from 3.5% in 2000 to 2.6% now. This article (with the charts from which I got the numbers) goes into possible reasons: https://www.themarshallproject.org/2017/12/15/a-mass-incarce...
Here’s the deal: it doesn’t matter if the US started killing every dissident outright. US behavior is not an excuse for unethical behavior in China. The government and citizens of China are not dumb children that can’t behave ethically if there are other unethical things going on in the world.