I once opened a speech by confessing to a crowd of Jews that I used to hate them. It was 2006 and I was a young native of Somalia who’d been elected to the Dutch Parliament. The American Jewish Committee was giving me its Moral Courage Award. I felt honored and humbled, but a little dishonest if I didn’t own up to my anti-Semitic past. So I told them how I’d learned to blame the Jews for everything.

Fast-forward to 2019. A freshman congresswoman from Minnesota has been infuriating the Jewish community and discomfiting the...