He actually posted this. He really did.
And first they came for the Nazis. And I did not speak out because I was not a Nazi? A slight simplification but that's basically what you're saying.
Or, "At first they came for the gays. And I did not speak up for the gays, because I was not gay." Or, "At first they came for the little girls. And I did not speak up for the little girls because I was not a little girl."
It is really hard to allow people to speak evil. Really hard. Really, really hard. But it also allows us to know them for the idiots and monsters they are. Because once they've said it, we can call them on it.