As American Creation we have a follow up written by Brad Hart on left-wing scholars who hold respectable positions in the academy who likewise engage in similar shenanigans. Hart's poster boy for a radical left wing version of Barton is Howard Zinn.
I am not going to term either Zinn or Barton "liars." That's a strong term. However I would agree that both are distortionists and propagandists. It may be impossible for historians not to read their biases into the record. But, it seems to me, using history for blatant propagandistic purposes is a lame thing to do.
Linked below is an example David Barton's "other" historical interests which just as badly distort the record as much as anything he's done with the American Founding. Barton is a partisan Republican and has held positions in the Texas Republican Party. Barton is now, also, an historian of the Civil War and "black history."
The Republican Party is not doing an effective job reaching out to blacks. I have no problem with Republicans trying to attract more minorities; I think it's a good idea. However, the video below well illustrates using history as propaganda to achieve political ends.
Barton's narrative connects modern day Democrats (the party who elected Barack Obama) with the racist Democrats who lost the Civil War and formed the KKK. What Barton doesn't mention is that it was the Southern White Male Conservative Christians (i.e., what Barton himself is) who actually are the heirs to the Confederates and the KKK. They were called "Dixiecrats." And they tended to be to the right of Republicans. Jerry Falwell, admittedly, was once such a racist Dixiecrat. The Dixiecrats are almost all Republicans now. I think most SWMCCRs have sincerely repudiated their racist past. Falwell, to his credit, repudiated his racist past. Not Trent Lott, but he was punished by the Republicans for his lack of repudiation. I don't think David Barton is a racist. And I don't think most SWMCCRs are racist. But blatantly distorting the record for political ends is not the proper way to do outreach.