The useful part of white identity’s vagueness is that whites don’t have to shoulder the burden of race in America, which, at the least, is utterly exhausting. A neutral racial identity is blandly uninteresting. In the 1970s, long after they had been accepted as “white,” Italians, Irish, Greeks, Jews and others proclaimed themselves “ethnic” Americans in order to forge a positive identity, at a time of “black is beautiful.” But this ethnic self-discovery did not alter the fact that whiteness continued to be defined, as before, primarily by what it isn’t: blackness.

Ms. Dolezal seems to have believed that the choice to devote one’s life to fighting racism meant choosing black or white, Negroid or Caucasoid. Black was clearly more captivating than a whiteness characterized by hate.

We lack more meaningful senses of white identity, even though some whites, throughout history, have been committed to fighting racism and advocating for social justice. In the 19th century, abolitionists like William Lloyd Garrison and John Brown helped end slavery. In the early 20th century, Mary White Ovington helped found the N.A.A.C.P. Lillian Smith depicted the South’s nexus of “sin, sex, segregation” in her writings. White Communists, priests and rabbis stood beside the Rev. Dr. Martin Luther King Jr. during the civil rights movement. Where would America be without these white allies of black freedom fighters?

Given that the monolithic definition of whiteness is antithetical to social justice, perhaps we should encourage a rebellion against it.