I've been giving thought to the Rachel Malonson story. In contrast to the situation of Rachel Dolezal, whose claim to black identity was not supported by her genetic heritage, Malonson had a black father and a white mother, and favored her mother in terms of skin tone. When she won the Miss Black University of Texas pageant-- which is explicitly open to persons with biracial status-- various comments were made about her not being "black enough." In other words, these protesters chose to define blackness in terms of an observable phenotype, in contrast to her genetic heritage. By this reasoning, Barack Obama, who has the exact same proportion of black/white parentage, *is* black because he displays a "black" phenotype, while Malonson is not.
The great irony of these half-witted protests is that in the long view they are criticizing the very right that the proponents of the 1960s civil rights movement fought for: the right of racial intermarriage, supported by breakthrough legislation like 1967's "Loving vs. Virginia." Further, the protesters are also guilty of emulating, however unintentionally, the same mindset favored by the opponents of racial intermarriage.
All U.S. laws that prohibited such intermarriages were also concerned with preserving the integrity of a certain phenotype. Long before the United States became an independent republic, early Americans knew that an offspring between one phenotypically black parent and one phenotypically white parent might display a white phenotype. The legal reaction was to prohibit such unions, in large part to keep the white race "pure."
The only way in which this differs from the position of Malonson's attackers is the degree of economic advantage. Intolerant American whites wanted to keep all property out of the hands of anyone who didn't pass a purity test. In contrast, intolerant American blacks are more concerned with keeping a set of privileges-- such as the "bragging rights" of winning a beauty contest for black women-- to be exclusive to women who meet a certain phenotype. I am not aware of any circumstance in which phenotypic-blacks have tried to block non-phenotypic blacks from owning any sort of property.
Nevertheless, once racial intermarriage became legal, American blacks as much as anyone ought to know that there could be no way of predicting which liaisons would be phenotypically black. In some subcultural black societies, blacks of dark hue sometimes experienced discrimination from light-skinned blacks, even if if the latter were not light enough to "pass." What we are seeing now is a tendency to replace one injustice with another, by claiming that there has so much history of dark-skinned blacks getting bad treatment that privileges associated with black subcultures cannot be allowed to anyone who may not have shared that history of suffering, whether that person is truly guilty of "passing" or not.
The more things change...