Such populations are targets cooptation by unscrupulous imperialist. Look at the US military's cooptation of the Hmong in SEA. Those that are radicalized against Earth reunification, in service of the imperialists, can't just be allowed to freely work to overthrow the reunified Earth Kingdom.

This has obvious real life parallels. In Vietnam, and more so in Laos, this led to actions against Hmong that were quite bad, and not always justified, but happened for reasons. This doesn't mean we reject the Vietnamese or the Laotian anti-imperialist struggles.