Though they were both Republicans and briefly campaigned together in 1952, President Dwight D. Eisenhower “loathed [Senator Joseph] McCarthy as much as any human being could possibly loathe another,” according to the president’s brother. Yet Eisenhower refused to criticize McCarthy to the press, telling aides he would “not get into the gutter with that guy.” Instead, Eisenhower opted for a clandestine campaign to stamp out the senator’s influence.

Far from appeasing McCarthy, as his critics asserted at the time, Eisenhower played a major role in effecting his fellow Republican’s downfall.

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Not long after World War II, anti-Communist paranoia swept through the United States, prompted by such events as the explosion of the first Soviet atomic bomb, the Communist takeover of China, the outbreak of the Korean War and the trial of the Rosenbergs.

In February 1950, at the height of the so-called Red Scare, McCarthy rose to prominence by falsely claiming to have a list of 205 known Communists working at the U.S. State Department. (When pressed for details, he later changed the number to 57.) The Wisconsin senator’s anti-Communist crusade only intensified from there, as he railed against allegedly subversive activity within various government entities.

“There were spies, and it was a real issue,” says David A. Nichols, author of Ike and McCarthy: Dwight Eisenhower’s Secret Campaign Against Joseph McCarthy. “But there’s no evidence I found that McCarthy ever caught one. It was all political bluster.”

McCarthy’s sway further increased in 1953, when he became chair of the Senate Committee on Government Operations, a position he used to subpoena witnesses, hold hearings, and make wild accusations against those he perceived as disloyal, many of whom lost their jobs and reputations.

McCarthy even attacked George C. Marshall, the architect of the Marshall Plan, not to mention Eisenhower’s former boss and mentor, essentially accusing him of treason. He also held up key Eisenhower appointees, most notably the U.S. ambassador to the Soviet Union, for allegedly being soft on Communism.

In public, Eisenhower wouldn’t even mention McCarthy’s name, thereby depriving him of the newspaper headlines he craved. When reporters asked about McCarthy, the president would answer, “I never talk personalities.”

“[Eisenhower] believed that if he gave McCarthy presidential attention, it would only encourage him, it would only elevate his prestige even more,” Nichols says, pointing out that Eisenhower’s predecessor, Harry Truman, constantly lambasted the Wisconsin senator to no ill effect.

Eisenhower’s opponents initially regarded his silence as tacit approval of McCarthyism’s excesses. In actuality, however, Eisenhower was biding his time to bring down McCarthy, whom he deemed a polarizing threat to both his presidency and the nation as a whole.

The president, a five-star general who led the D-Day invasion of Europe during World War II, became especially incensed in late 1953, when McCarthy accused the U.S. Army of harboring Communists. By January 1954, Eisenhower decided to fight back.

Meeting in the attorney general’s office on January 21, 1954, trusted Eisenhower aides learned of sensitive information they felt could be weaponized: Roy Cohn, chief counsel to McCarthy’s investigative subcommittee and a leading proponent of his boss’s anti-Communist actions, had with McCarthy’s help secured special Army privileges for G. David Schine, an unpaid consultant to the subcommittee. (Nichols believes that Schine and Cohn were lovers.)

With Eisenhower’s backing, aides started preparing a report on what would become a major scandal. Meanwhile, on March 9, Ralph Flanders, a Republican senator from Vermont, denounced McCarthy—assuredly, Nichols says, having received White House encouragement to do so. “To what party does he belong?” Flanders declared on the floor of the Senate. “One must conclude that his is a one-man party, and that its name is McCarthyism.”

That same evening, broadcast journalist Edward R. Murrow launched his own legendary anti-McCarthy diatribe, saying “the line between investigating and persecuting is a very fine one, and the junior senator from Wisconsin has stepped over it repeatedly.” “We will not walk in fear, one of another,” Murrow added. “We will not be driven by fear into an age of unreason.”

With Democrats ramping up their attacks as well and McCarthy now on his heels, Eisenhower stuck the knife in further. On March 11, he surreptitiously greenlighted the release of the Schine report, which documented how Cohn (who later served as Donald Trump’s personal attorney early on in the real estate mogul's career) repeatedly threatened to “wreck the Army” if his and McCarthy’s requests regarding the recently drafted Schine were not approved.

“It was pretty brutal politics,” Nichols says, referring to Cohn and McCarthy, as well as the White House response. “We think our politics is brutal now, but it was in those days too.”

As a result of the scandal, 36 days of televised hearings were held, running from April to June, during which McCarthy continued raging against his perceived enemies. As Nichols points out, though, “TV was not kind to him. It showed him to be a bully and hurt him a great deal politically.” In one particularly poignant moment, a lawyer for the Army asked him, “Have you no sense of decency, sir?”

Just weeks after the hearings concluded, Senator Flanders introduced a resolution to censure McCarthy for conduct unbecoming of a senator. That December—with Eisenhower’s behind-the-scenes support—the Senate condemned him by a vote of 67 to 22, after which “Ike” praised the chair of the censure committee for doing a “very splendid job.”

A few days later, McCarthy publicly repudiated Eisenhower. But by then, McCarthy, who just a year earlier had been one of the most powerful and popular politicians in America, had lost nearly all of his influence. According to Nichols, his fellow lawmakers wouldn’t even sit with him in the Senate dining room or listen to him on the Senate floor.

At the end of his life, Nichols says, “Eisenhower never admitted that the White House was behind this.” Yet he couldn’t help but gloat a bit in private. On at least one occasion, he reportedly repeated a joke that “it’s no longer McCarthyism, it’s McCarthywasm.”

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