As an ideology, black nationalism encompasses a diverse range of beliefs which have variously included forms of economic, political and cultural nationalism, or pan-nationalism.[9][7] It often overlaps with, but is distinguished from, similar concepts and movements such as Pan-Africanism, Ethiopianism, the back-to-Africa movement, Afrocentrism, Black Zionism, and Garveyism.[5] Critics of black nationalism say it promotes racial and ethnic nationalism, separatism and black supremacy, and they compare it to white nationalism and white supremacy. However, the Southern Poverty Law Center says that black nationalist groups exist in a "categorically different" environment than white nationalists in the United States.
I'm white, my dad (also white) played blues guitar, and I've never run into anything remotely like what you're describing.
And if it turns out that the SPLC was totally wrong, and 'Black Nationalism' takes over and commits genocide on white people, that's definitely something we'll be worried about.