Depends. If they're building satellites that grapple dead satellites, that can certainly be used to attack active satellites too. But laser brooms wouldn't be effective against anything larger than a few centimeters. A space broom might be a cover for a more powerful directed energy weapon, but not necessarily so.
Anyway, China is already toying around with the first sort, and they didn't ask anybody for permission. Their 'authority' to do it is being a sovereign nation.
