I've been reading an older biography of Adlai Stevenson II, the Democratic presidential nominee in 1952 and 1956. He was known for his eloquence and for being one of the few pols willing to openly criticize and call out Senator Joseph McCarthy at his height of power. In February 1954, in response to GOP attacks on the loyalty of Democrats (including former President Truman) at a Lincoln Day fundraiser, Stevenson gave a remarkable speech about how McCarthyism was warping and undermining the Republican Party and American politics as a whole, and it's very pertinent to today. I've quoted the highlights below, but it easily sounds like a speech that could be given about our current situation.
"This has been a fateful week in the history of American government. We are witnessing the bitter harvest from the seeds of slander, defamation, and disunion planted in the soil of our democracy...Those of us - and they are most of us - who are more Americans than Democrats or Republicans count some things more important than winning or losing elections. It is wicked and it is subversive for public officials to try deliberately to replace reason with passion; to substitute hatred for honest difference...When one party says the other is the party of traitors who have deliberately conspired to betray America, to fill our government services with Communists and spies...they violate not only the limits of partisanship, they offend not only the credulity of the people, but they stain the vision of America and of democracy.
That such things are said under the official sponsorship of the Republican Party in celebration of the birthday of Abraham Lincoln adds desecration to defamation. This is the first time that politicians, Republicans at that, have sought to split the Union - and in Lincoln's honor. This system of ours is wholly dependent upon a mutual confidence in the loyalty, the patriotism, the integrity of purpose of both political parties. Extremism produces extremism, lies beget lies. The infection of bitterness and hatred spreads all too quickly from one area of our life to another. And those who live by the sword of slander also may perish by it, for now it is being used against distinguished Republicans. We have just seen a sorry example of this in the baseless charges hurled against our honored Chief Justice [Earl Warren]. When demagoguery and deceit become a national political movement we Americans are in trouble; not just Democrats, but all of us."
Change a few words here and there and that speech would be even more relevant today than it was then. Perhaps it's worth noting that McCarthy's chief aide and adviser was Roy Cohn, who later became a personal attorney and adviser to Donald J. Trump. So while McCarthy himself may have self-destructed, the seeds he planted in some sense bore fruit in Trump and Trumpism.