Were the Republicans denouncing Omar even sincerely opposed to anti-Semitism, they would not support Donald Trump. Trump, after all, in 2013 tweeted that “I’m much smarter than Jonathan Leibowitz—I mean Jon Stewart.”
He ran for president on a slogan laden with anti-Semitic associations from the 1930s: “America First.” In 2015 he told a Jewish audience that “You’re not gonna support me because I don’t want your money… you don’t want to give me money, but that’s ok, you want to control your own politicians that’s fine.”
In 2016 he retweeted an image of Hillary Clinton surrounded by money and a Jewish star. He closed his presidential campaign with an ad that showed three Jews—Janet Yellen, Lloyd Blankfein and George Soros—alongside language about “global special interests” that “control the levers of power in Washington.”
In 2017, he said there were “very fine people” among the neo-Nazis who marched in Charlottesville. And in 2018, his racist fear mongering about a caravan of Central American migrants provoked a Pittsburgh man to commit the worst anti-Semitic atrocity in American history. Unlike Omar, he has not apologized for any of this.
If you denounce Ilhan Omar but support Donald Trump, you don’t really oppose bigotry. You don’t even really oppose anti-Semitism. What you oppose is criticism of Israel. That’s the real reason Republicans are so much more outraged by Omar’s tweets than by Trump’s. They’re not trying to police bigotry or even anti-Semitism. They’re using anti-Semitism to police the American debate about Israel.