To hear some conservatives tell it, the Republican Party's history on race relations is nothing to be ashamed of. Sure, Strom Thurmond and other racists switched from the Democratic to the Republican coalition at the very moment when Democrats were abandoning segregation and embracing civil rights for blacks. But that wasn't because of race. It was because of [insert something about "constitutional principles" and "states' rights" here].

Frank Rich dismantles that argument in this week's New York Magazine, and Jamelle Bouie pondered the implications of it last week:

I’m still unsure of what this revisionism is supposed to accomplish. If it’s to appeal to actual African American voters, you might want to try a different approach, since this one won’t work. But if it’s to assuage guilt and assure conservatives that they are, and have always been, on the right side of history, then -- to borrow from President Obama -- please proceed.

It's a lost cause, in part because the historical record is so voluminous. Pat Buchanan, who has always been more forthright about these things than most of his peers, told George Packer that Nixon understood early in the 1960s that he could cobble a winning coalition from Midwestern and Northeastern Catholics and “Wallace Democrats in the South.” The racial resentment both groups shared was a bonding agent for Republican presidential campaigns for years.

After Nixon was elected president, Buchanan drafted a memo pointing out that by exploiting racial polarization, Republicans could “cut the Democratic Party and country in half.” Subsequent Republican paeans to the Confederate flag, obligatory visits by Republican candidates to Bob Jones University (where interracial dating was prohibited until 2000) and the myriad code words and dog whistles of the right will not easily bend to the new revisionism.

No doubt recognizing that, in 2005 Ken Mehlman, then the Republican Party chairman, publicly apologized for his party’s history of racial polarization. "Some Republicans gave up on winning the African-American vote, looking the other way or trying to benefit politically from racial polarization," Mehlman told the annual convention of the National Association for the Advancement of Colored People. "I am here today as the Republican chairman to tell you we were wrong."

Mehlman’s candor never took root. Self-delusion remains the operative Republican response to losing more than 90 percent of the black vote and more than two-thirds of Hispanic and Asian votes in the 2012 election. (In a recent poll, more than two-thirds of Hispanics said Republicans were either indifferent or hostile to Hispanics.)

This history is now viewed as an albatross around a party ill-prepared for the multiracial electorate of the 21st century. But its effects on the South, and on race relations generally, is mostly overlooked. President Barack Obama last week spoke of creating a “permission structure” to enable congressional Republicans to support legislation that he also supports. For more than four decades Republicans maintained a permission structure for racial resentment, signaling to white racists that their views were not only acceptable but condoned. The national opprobrium that attached itself to the white-supremacist South in the 1950s and early 1960s eased as Republicans became the champions of white southern culture, all-inclusive.

Wallace Democrats didn't just find a political home in the Republican Party. They found years of sustenance for ugly racial attitudes and support for continued resistance to cultural change. Politics being what it is, someone was bound to exploit this electorally rich vein of racial resentment (Democrats, after all, had long exploited racism for political gain). It's understandable that Republicans don’t want to celebrate the accomplishment. It's also counterproductive to pretend it never happened.

(Francis Wilkinson is a member of the Bloomberg View editorial board. Follow him on Twitter.)