I recently visited my ex-girlfriend, who is part Navajo, when passing through the city she lives in now and we had a good laugh about this. When we were dating, she never talked about being Native American because she didn’t think it would benefit her in any way. We actually argued about whether she should apply for the Native American scholarships available to her and she was against it at the time. But, since the Democratic Party identity politics craze began, she warmed up to the idea and now she shamelessly uses it to her advantage. I hate identity politics and so does she, but I was pleased to learn she became comfortable with it for her own sake. In her case, she never passed for white anyhow.

Or, maybe because its been economically, socially and legally advantageous to be considered white for hundreds of years, so people who weren't white were saying they were (if they could get away with it). What we're seeing now may be a pendulum swing, and if so, good.