"blood quantum" vs "one drop"
These are core tools white supremacy uses to dictate who is and isn't white.
During European colonization and enslavement,
African Americans were categorized according to the “one-drop rule,” where one-sixteenth African ancestry might have qualified one as Black. Native Americans, on the other hand, were codified using blood quantum, where one-quarter Native American ancestry might not have been enough to designate a person as Indigenous. ...Both constructions of race were tied to European economic realities, [Dr. Belén] Unzueta says. “African Americans were exploited for labor, while Native Americans were exploited for land. If you’re looking to exploit land, it’s better for people to disappear. If you’re looking to exploit labor, it’s better if the population grows.”
Here in the U.S. -- and in American-dominated spaces, like academic publishing and much of the Anglophone internet -- our understanding of oppression is still centered on controlling categories.
White supremacists focus on silencing discussion of oppression, and erasing oppressed groups.
Opponents of white supremacy often focus on which groups "count." Which ones are oppressed enough to matter. Based mainly on vibes.
The system imposed on Native Americans, blood quantum, was a way to diminish the number of Natives to whom the government owed something in exchange for land.
-- Kliph Nesteroff, We Had a Little Real Estate Problem: The Unheralded Story of Native Americans & Comedy
Any system of "who counts" that isn't based on listening to a group about their personal experiences of oppression is just oppression quantum.