I'm asking this in KiA2 as to avoid the Jewish conspiracies since that isn't what this post is about (and Santa Inc. is obviously KiA-related).

I'm sure most people know the fallout of Santa Inc. and Seth Rogan's tweets about all the white supremacists. This begs the question (for me anyway):

Seth Rogan is a white guy, how the hell is he "Jewish" and not white? If you look up the history of the surname "Rogan", you get this: "[Rogan is of] Irish origin, and is an Anglicised form of the Gaelic name "O'Ruaghagain".

So can any white guy just convert to Judaism and start calling themselves Jewish and they are suddenly not white anymore? The whole "Jewish, not white" thing has never made sense since Judaism is a religion, not a color.

Or am I missing something?

*edit - thanks for all the replies guys, that makes sense.