It’s one of the most well-known – and written about chapters in American political history. Less covered, is the strong Massachusetts connection.

Wisconsin Senator Joseph McCarthy didn’t create the post WWII red scare in America, but he did ride it to power.

Pulitzer Prize winning historian David Oshinsky, author of “A Conspiracy So Immense: The World of Joe McCarthy” says that McCarthy came to the issue in 1950 in completely political terms.

By 1954 McCarthy had fully come to believe in the Communist conspiracy. That this was no game to him anymore.

In ‘53, McCarthy had been named chair of the Senate’s Permanent Subcommittee on Investigations. And boy did he investigate. More than 150 hearings in just two years – seeking to ferret our spies and subversives in government agencies. But when an increasingly brash and blustering McCarthy went after the US Army, president Eisenhower, a member of McCarthy’s own party who had largely let McCarthy be, would have none of it.

What Eisenhower did in a stroke of genius is demand that these hearings be televised. Because what Eisenhower knew, viscerally, is that McCarthy would hang himself on television.

What the Army needed was a shepherd to lead the sheep to slaughter.

“You kind of need a folksy attorney, someone Americans can really identify with, someone who seems to have no dog in the fight. Someone who just wants to get at the truth and expose hypocrisy,” Oshinsky says.

The Army found their man in Iowa-born, Harvard educated, long-time Boston attorney Joseph Nye Welch. Oshinsky says Welch would describe himself as just a country bumpkin lawyer who got lucky.

“In fact he was this brilliant defense attorney and he used that kind of “just folks” to great advantage.”

McCarthy charged that the Army had been to slow to weed out Communists from their ranks – and to be fair, Oshinsky says he wasn’t exactly wrong. The Army countered that McCarthy was using his influence and power to keep a staffer from getting drafted. The hearing was to get to the bottom of it.

“What they really showed were the power of television,” Oshinsky says. “And how good Joe Welch could be on television and how bad McCarthy was.”

The hearings stretched on for months. But it all came to a head on June 9. Welch was scoring points relentlessly questioning McCarthy’s attorney, when out of nowhere McCarthy bursts in charging that a young lawyer on Welch’s own team had once been a member of a communist organization. The lawyer had, like many… briefly, in college. Welch knew about it. He knew McCarthy knew about it. And he knew McCarthy knew the lawyer was no communist. Welch retorted with one of the most famous lines in American political history.

WELCH: Let us not assassinate this lad further. You’ve done enough. Have you no sense of decency, sir? At long last. Have you left no sense of decency?

Oshinsky says the audience broke out in applause “In other words, it was someone really taking on Joe McCarthy in a very public way about the kinds of tactics he would use.”

Eisenhower was right. Joe McCarthy would never recover from the exchange.

“I think you can make the argument that June 9, 1954 was the incident that crystalized everything that was wrong about McCarthy and McCarthyism.”

By the end of the year McCarthy was officially “condemned” by Senate vote. Three years later, he was dead from the effects of alcohol abuse at the age of 48. For his part, Joseph Welch was so good on TV, Otto Preminger tapped him to play the judge in his 1960 screen classic “Anatomy of a Murder,” a performance that earned Welch a Golden Globe nod.

The beginning of the end of Senator Joseph McCarthy, ushered in with a famous turn of phrase by Boston lawyer Joseph Welch, 61 years ago this week.

If you have a tale of forgotten Massachusetts history to share, or there’s something you’re just plain curious about, email Edgar at curiositydesk@wgbh.org. He might just look into it for you.