Who Is "Dr." David Barton?

Late last year, I wrote a post questioning why David Barton of WallBuilder's was trying to pass himself off as a professor ... and another post shortly thereafter wondering why he was being refered to as "Dr." Barton when his academic credentials consist entirely of a "B.A. from Oral Roberts University and an Honorary Doctorate of Letters from Pensacola Christian College."

There is no evidence that we have ever seen that Barton earned a Ph.D ... yet for some reason we keep seeing instances in which he is billed as "Dr. David Barton":

Unionville Christian Church will observe the National Day of Prayer May 6 at 6:30 p.m. There will be a showing of "Is America a Christian Nation?" by Dr. David Barton followed by prayer for the community, government leaders and nation lead by David L. Williams.

Just yesterday, Barton addressed a prayer breakfast in Tennessee and again he is being refered to as "Dr." Barton: 

Americans have "moved away from knowing our own history" in believing the Founding Fathers were a group of non-religious men and women, the head of a national pro-family group says.

Dr. David Barton, speaking Tuesday to a record crowd of 1,800 at the 32nd annual Chattanooga Area Leadership Prayer Breakfast, said truths about the country's founders have been removed from history textbooks, misinterpreted by courts and distorted by the media.

...

Dr. Barton said Americans still have the opportunity to follow George Washington's challenge to his beleaguered men following their winter at Valley Forge: "To the distinguished character of patriot, it should be our highest glory to add the more distinguished character of Christian."

"Become a part of what made America great," Dr. Barton said. "We need religion and morality ... to thrive as Americans."

Did Barton earn a doctorate that we don't know about?  Are people just mistakenly calling him "Dr." Barton?  Or is Barton falsely billing himself as "Dr." Barton?  Is he using the honorary Doctorate from Pensacola Christian College to justify this title? 

What is going on here?