“If history were to repeat itself,” warned President Franklin D. Roosevelt in his 1944 State of the Union address, “and we were to return to the so-called normalcy of the 1920s, then it is certain that even though we shall have conquered our enemies on the battlefields abroad, we shall have yielded to the spirit of fascism here at home.”

The “normalcy” of the 1920s that Roosevelt referred to was a time of peace and prosperity. The decade began with Republican President Warren Harding commuting the sentences of political prisoners jailed by the Wilson administration, including the socialist leader Eugene Debs. “Normalcy” meant the end to the Palmer raids aimed at rooting out dissidents, the end of economic rationing, the cessation of domestic surveillance and the state propaganda of the World War I years.

Also, “A return to normalcy” was Harding’s campaign slogan in the 1920 presidential election, which he won in a landslide over Democrat James Cox and his running mate – Franklin D. Roosevelt.

That Roosevelt nurtured resentments against the Republicans for the drubbing he received in 1920 is no surprise. That those resentments ran deep enough for him to smear Republicans in 1944 with the “spirit of fascism” at the height of the war against the real thing is nothing short of disgusting.

But it was effective.

Harry Truman recognized that when he ran for president against the liberal Republican Thomas Dewey in 1948. Truman charged that Dewey was the front man for the same sort of “powerful reactionary forces” that orchestrated the rise of Hitler in Germany.

When a communist assassinated President Kennedy, somehow the American right got the blame. Lyndon Johnson translated that myth into a campaign of slander against Barry Goldwater, casting him as a crypto-Nazi emissary of “hate.”

After the Oklahoma City bombing, President Clinton saw fit to insinuate that Rush Limbaugh and his imitators were partly to blame.

Such partisanship is hardly reserved for partisans. The late Daniel Schorr, then of CBS News, reported that Goldwater’s planned European vacation was really a rendezvous with the German right in “Hitler’s onetime stomping ground.”

Schorr spent his golden years at National Public Radio. No doubt he would have been pleased with the “reporting” of its counterterrorism correspondent, Dina Temple-Raston. Before the identities of the Boston bombers were confirmed, she said her sources were “leaning” toward believing that it was a homegrown “right-wing” attack, and cited that “April is a big month for anti-government and right-wing individuals.”

How so? Well, because April’s when the Oklahoma City bombing took place, as well as the Waco siege, the Columbine shootings and, how could one forget, Adolf Hitler’s birthday.

Over the last few years, the invariably unjustified rush to pin violence on the “right wing” – particularly the Tea Partiers – has reached the point of parody. Remember when New York City Mayor Michael Bloomberg speculated that the foiled Times Square bomber might just be angry about Obamacare?

As the Washington Examiner’s Philip Klein recently noted, among the myriad reasons conservatives take offense at this idiotic knee-jerk slander is that the term “right wing” is also routinely used to describe both terrorists and mainstream Republicans such as Paul Ryan and Mitt Romney. I can exclusively report that neither of them celebrates Hitler’s birthday.

Every Muslim terrorist enjoys not just the presumption of innocence until proven guilty but the presumption that he’s a fan of Ayn Rand, too.

Ah, but some would respond that “right wing” is different than “Muslim” because there’s so much similarity between mainstream conservative ideology and the terror-filled creeds of the far right.

Except there isn’t. Timothy McVeigh, an atheist, wasn’t part of the conservative or libertarian movements. He wasn’t even part of the militia movement. And what on earth was right wing about the Columbine shootings?

In plenty of cases of multiple killings, from the Unabomber to Christopher Dorner, the perpetrators espoused views closer to the mainstream left’s than McVeigh had to the mainstream right. Occupy Wall Street was an idealistic expression of democratic protest, but the Tea Partiers were brownshirts in khakis.

And, recall that Secretary of State John Kerry belonged to a group – Vietnam Veterans Against the War – that once discussed assassinating American politicians. Barack Obama was friendly with a convicted domestic terrorist. But to even bring these things up, never mind invest them with significance, is considered outrageous guilt by association.

And you know what? Maybe it is.

But if that is outrageous, what do you call the paranoid style of liberal politics that has confused normalcy for fascism for more than half a century?

© 2013 Tribune Media Services, Inc.