In an online column last week, Eric Alterman and co-author Mickey Ehrlich denied any parallel in levels of partisan support for the "birther" and "truther" misperceptions:
David Paul Kuhn at Time.com attempted evenhandedness by introducing the results of supposed “truther” polls conducted in 2007. His claim is that the same number of Democrats believed that Bush knew about the 9/11 attacks in advance as Republicans believe Obama is not a citizen. However, this comparison doesn’t work. While Bush was handed a memo explaining that Osama bin Laden was determined to attack in the continental United States and decided to go fishing that day, no evidence exists anywhere to dispute Obama’s citizenship.
However, the parallel isn't based simply on one potentially ambiguous poll question (a Rasmussen poll asking "Did Bush know about the 9/11 attacks in advance?"). As I showed back in August, Democratic support for the proposition that "People in the federal government either assisted in the 9/11 attacks or took no action to stop the attacks because they wanted to United States to go to war in the Middle East" in 2006 was quite comparable to birther misperceptions among Republicans in recent polls. What's bizarre is that the Kuhn post linked by Alterman and Ehrlich cites me making precisely this point. Did they even read it?