White is a specious concept like race itself. It is wholly political and one of the primary building blocks of white supremacy in a race constructed society. white provides state-sanction for systemic white advantage.
White is not an ethnicity. Or a color. It is not scientific or theological. Outside of its political parameters it does not exist.
White is unlike Black, for example, which is used to forge an identity to fight and resist white supremacy by people worldwide. Black origins are in the experience of the African Diaspora.
There is white culture and Black culture. The latter is rooted in liberation; the former is rooted in oppression. The collective struggle against white supremacy gives life to anyone who fights it (of any "race").