In the 2008 Democratic presidential primary, the moment when the momentum shifted decisively against Hillary Clinton was when the New York Senator embroiled herself in a controversy over whether President Lyndon Baines Johnson or Dr. Martin Luther King, Jr. deserved more credit for passing civil rights legislation.

Today, that debate continues, exposing the enduring frustrations and suspicions that Democrats often try to conceal by casting Republicans as the civil rights villains.

In a debate on the eve of the New Hampshire primary–when she would defy the polls to deliver Obama a stunning defeat–Clinton began contrasting Johnson to King as a way of contrasting herself, favorably, with Obama.

“Dr. King’s dream began to be realized when President Johnson passed the Civil Rights Act,” she said, adding that “it took a president to get it done.”

The conclusion she wanted voters to draw was that while Obama might give a good speech, he had not achieved much else. It was a somewhat inappropriate comparison, one that minimized the role of activists in the streets.

The Obama campaign blew the controversy completely out of proportion, however, by seizing on Clinton’s remarks as if they were evidence of some deeper racism. They portrayed the Clintons as if they were blowing dog whistles by criticizing Obama’s record.

It was a total farce, but it worked to galvanize the black voters of South Carolina–the next major primary–behind Obama.

And it wasn’t long before Rep. John Lewis (D-GA), the civil rights veteran who helped lead the march in Selma, switched his loyalties from Clinton to Obama.

Today, Lewis is embroiled in the escalating controversy over the movie Selma, which critics have said portrays President Johnson too negatively, especially relative to Dr. King. (Director Ava DuVernay told Rolling Stone that she departed from historical facts because she “wasn’t interested in making a white-savior movie.”)

Lewis admits that the film may lack “completeness” regarding Johnson’s role, but says that Selma is being judged too harshly for its inaccuracies, implying (as others have done) that it is the victim of a racial double-standard.

And thus has Johnson been excised from the civil rights pantheon.

Maureen Dowd of the New York Times has lamented, appropriately: “It was clear that a generation of young moviegoers would now see L.B.J.’s role in civil rights through DuVernay’s lens.”

To some extent, the ongoing fight echoes the old racial divide that really did exist among Democrats, who struggled to square the demands of post-New Deal black voters with the party’s segregationist Southern establishment.

But what has also happened is that a generation of Democrats has emerged in Obama’s wake that does not understand Johnson–or his failures, such as the Great Society.

It is a generation fascinated by “struggle” but bored by governing, amused by “truthiness” but ignorant of truth.

Clinton saw that earlier than most, because she was the first victim of Obama’s movement-style politics–and of his fawning media, which even Media Matters railed against for a while.

Her mistake was to think that Democrats shared her contempt for Obama, which was not racial but simply personal: he had done nothing to earn his way to the top, had paid no dues, had not even suffered as King had done, and yet dared to compare himself to that great American through rhetoric alone.

Her own tone-deafness led her into a terrible tactical blunder that re-opened the party’s racial divide, and allowed Obama to claim King’s legacy even more strongly (the media had not yet decided that Jeremiah Wright deserved attention).

But there was a valuable lesson, too, in Clinton’s reference to Johnson–one that Obama ignored: namely, the importance of compromise.

Obama’s failures at governance leave behind a party with little to sustain itself but nostalgia for the imagined past–and its conflicts.

Senior Editor-at-Large Joel B. Pollak edits Breitbart California and is the author of the new ebook, Wacko Birds: The Fall (and Rise) of the Tea Party, available for Amazon Kindle.

Follow Joel on Twitter: @joelpollak