In legal matters, the law decides. That's how we knew who could go to schools for white people.

That a person's religion isn't dependent on their ancestry is the reason bigotry is not the same as racism.

And yes, preudice is an attitude, but the law can dictate the behavior.

“If a white man wants to lynch me, that's his problem. If he's got the power to lynch me, that's my problem. Racism is not a question of attitude; it's a question of power. Racism gets its power from capitalism. Thus, if you're anti-racist, whether you know it or not, you must be anti-capitalist. The power for racism, the power for sexism, comes from capitalism, not an attitude.” ― Stokely Carmichael