And yes, it does not make sense to talk about a European identity since the historical experience among different European nations was so diverse. On the other hand, it makes perfect sense to talk about an African identity IN THE US because the African slaves came and lived (or died) as individuals and not as part of an ethnic group. In fact, many times even the slaves' family was separated as they were sold to different masters. Notice also that for both the Latinos and Native Americans, the identity is more about their particular tribe or ethnicity. For example, a Latino from Mexico will identify himself as Chicano (
Chicano - Wikipedia). We tend to call everybody "Mexican" but that is only because we "whites" give them such identity.
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You do not need to have a personal connection for the identity . Perhaps her anscestors were not slaves in the US but other Somali Blacks were.
First of all, let's put things in the right perspective. The slavery in American was one of the most brutal forms that ever existed. The slaves in the Ottoman Empire and North Africa had rights that no slave in the US could enjoy or even dream that he could enjoy.
Mamluk - Wikipedia
Mamluk (Arabic: مملوك mamlūk (singular), مماليك mamālīk (plural), meaning "property", also transliterated as Mameluke, mamluq, mamluke, mameluk, mameluke, mamaluke or marmeluke) is an Arabic designation for slaves. The term is most commonly used to refer to non-muslim slave soldiers and Muslim rulers of slave origin
Now, after addressing the poor comparison of the different forms of slavery, I can agree with you that IF there was a white community in North Africa with roots to slavery, then THAT white community in THAT region would have a valid "white" identity because that identity would have been anchored on a common historical experience.