[knagra]

Those labels are less problematic because they are much better defined (e.g., "German Jews" == persons who practice(s|d) Judaism in Germany), self-applied labels (e.g., anti-Communist), or a combination of both (Cold War liberalism).

[javajosh]

The question of what counts as "Jewish" is, itself, incredibly complex. As for self-applied labels, what does that even mean? If you call yourself something once, are you that thing forever? Do you even know what it implies to call yourself "Anti-Communist"?