CNN anchor Jake Tapper called out Republican lawmakers staying silent on President Donald Trump with a history lesson on infamous demagogue Sen. Joseph McCarthy.

“From the moment that Wisconsin Senator Joe McCarthy began his smear campaign in February of 1950 up until his censure by the U.S. Senate in 1954, the story of McCarthy was not just the story of indecency and lies and law breaking. It was also the story about just how much Republican lawmakers were willing to take,” Tapper said in a closing monologue on State of the Union Sunday.

The term “McCarthyism” comes from the Wisconsin Republican senator’s wild and often unsubstantiated claims of Communist infiltration of the U.S. in the 1950s.

“When you go back and read about that period, what really stands out is how much McCarthy’s contemporaries are judged today by how they handled him,” Tapper continued. “There are empirical wrongs in the world. Smearing innocent people is one of them. Using your political office to push foreign nations to dig up dirt on your political opponents is another one.”

“You know this. I know this. And I would bet that most Republicans on Capitol Hill know this,” Tapper said, apparently addressing Republicans who have declined to speak about Trump pressuring foreign powers to investigate an opponent.

“Because history will one day come looking for them, too,” he said. “She will want to know what they said and did during this time. And she will likely not be in a forgiving mood.”

Watch above, via CNN.

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