After announcing his retirement from the Senate on Tuesday in a rousing speech criticizing the Republican Party’s transformation under President Donald Trump, Sen. Jeff Flake (R-AZ) followed up with an op-ed in the Washington Post drawing a parallel between Trump and Joseph McCarthy.

Flake began the op-ed by describing a speech from Joseph Welch, who famously told McCarthy, “You’ve done enough. Have you no sense of decency, sir, at long last? Have you left no sense of decency?”

“The moral power of Welch’s words ended McCarthy’s rampage on American values, and effectively his career as well,” Flake wrote in his Tuesday evening op-ed. “After Welch said his piece, the hearing room erupted in applause, those in attendance seemingly shocked by such bracing moral clarity in the face of a moral vandal. Someone had finally spoken up and said: Enough.”

Flake said that Welch “reawakened the conscience of the country.”

“We face just such a time now. We have again forgotten who we are supposed to be,” the senator wrote. “There is a sickness in our system — and it is contagious.”

Flake did not mention Trump by name, but criticized the President’s attacks on Gold Star families and his “childish insults” aimed at foreign leaders.

“How much more damage to our democracy and to the institutions of American liberty do we need to witness in silence before we count ourselves as complicit in that damage?” Flake asked. “Nine months of this administration is enough for us to stop pretending that this is somehow normal, and that we are on the verge of some sort of pivot to governing, to stability.”