Some white nationalists adopt a more restrictive definition of "white" that excludes, e.g., Slavs, Jews, etc. National Vanguard says:
All theory aside, a practical, utilitarian method for the Movement of deciding whether or not someone is of acceptable White descent is by examining the following criteria:
1. Do they look White?
2. Do they self-identify as White?
3. Do they have any immediate non-White ancestry?
4. Are they culturally White?
5. Do they display White values and behavior?
6. Are they accepted as White by their neighbors and co-workers?
7. Are they committed to the racial struggle?
This lends itself to a "No true Scotsman" situation where, if they say that looking at child porn is not white behavior, then they might be more likely to exclude that person from counting as white.
E.g. maybe a half-Jew who didn't look at child porn, they might have considered white, but if he did look at child porn, they'd consider him Jewish.
It's kind of a confirmation bias.
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