If you’re not a textualist, there is a coherent reading that it only applies to American descendants of slaves. But that would mean that it doesn’t protect asians, hispanics, etc!

A logical and factual error made by proponents of affirmative action is to start with the premise that the civil rights laws were intended to help american descendants of slaves, but then extend them to other non-whites by categorizing them as “functionally black.” This is utterly incoherent, because black descendants of slaves and native americans are sociologically and economically distinct from other non-whites. Hispanics are just time-shifted Italians and Irish: low skill immigrants that economically assimilate within a few generations. By contrast, the gaps between black descendants of slaves and native Americans and other americans are not shrinking over time. They remain as large today as in 1965.

There’s a coherent version of affirmative action that gives a preference to descendants of slaves and native Americans but nobody else. But that bears no resemblance to the “diversity” based system that actually exists, which irrationally privileges Cubans over Bangladeshis because Indians are richer than Mexicans.