Mr. Benson mentions right at the top "Many conservatives are aghast, not just on account of Trump's obnoxious birtherism.....".
I don't think Donald was being at all disingenuous in being one of many discussing Birtherism and Obama. In fact, I think the entire issue needs to revisited.
What is factual is that no adequate checks on Obama were undertaken before he became President, and none since. No real birthed would suggest for certain he was born elsewhere, only that he hadn't proven he was born in the USA. And frankly, that still stands as of March 2013. The long form birth certificate produced in 2010 has been called "most likely a forgery" by the only American law enforcement agency to investigate it.