On Thursday night, President Trump turned on one of his most important allies.

A day after a three-judge panel from the U.S. Court of International Trade, which included a judge he appointed in his first term, rejected his use of the International Emergency Economic Powers Act of 1977 to grant him expansive tariff authority, Trump posted a rambling screed on Truth Social condemning the judiciary.

He posted his rant in spite of the fact that the court’s decision was almost immediately stayed by a court of appeals while it considers the administration’s arguments. Even so, the initial ruling was too much for Trump; he had to unleash.

That’s not new. He’s been condemning judges who rule against him since before he first became president. This time, however, he went after Leonard Leo and the Federalist Society. The Federalist Society is easily the largest and most influential organization of conservative lawyers in the country (I was a member in law school), and Leo is long one of its key leaders.

Trump declared himself “so disappointed” in the Federalist Society because of its “bad advice” on judicial nominations. But he reserved his real venom for Leo, calling him a “sleazebag” and a “bad person who, in his own way, probably hates America.”

Leo helped Trump choose conservative lawyers and judges for both the judiciary and his administration. Trump’s decision in his first run for president to publish a Supreme Court short list stocked with leading lights of the Federalist Society helped him win over skeptical conservatives in 2016.

But there was a problem. The Federalist Society never capitulated to Trump. It’s a decentralized group, and its members are stubbornly independent. I’ve spoken to dozens of Federalist Society student groups, and they can vary wildly from school to school. One chapter can be reasonably Trump-friendly (but never, in my experience, fully MAGA), while another is mainly Never Trump.