In all of my years of experience, I haven't met a bigot who didn't know they were being bigoted and why it was bigoted. I have met so very many who when confronted with their bigotry fail very badly at claiming that they don't know. Instead of sticking to their guns they decide to become the world's worst improv actor - it's very easy to spot. Their whole idea is to become as slippery as possible with ignorance and it shows.