This is a moralistic argument, and may be more or less convincing depending on personal values. My argument against racism would be a practical one: racism is

This is a moralistic argument, and may be more or less convincing depending on personal values. My argument against racism would be a practical one: racism is used to divide the working class against itself, it's another wedge issue just like gay marriage or abortion. It's necessary to combat this divisive rhetoric, because otherwise we won't have the strength to collectively resist the real evils.