Could someone point to me someone -- anyone -- of any stature in the Republican Party or the conservative movement who has shopped the idea that Barack is a Muslim (it was, of course, Hillary Clinton who said he was a Christian "as far as [she] know[s]")? Or a terrorist who's hand-in-glove with Osama bin Laden?
Of course, there are idiots who buy into all kinds of weird theories of the sort alluded to by Matthews. But remember -- such people also exist on the left. They're the ones who are concerned that "John McCain was brainwashed by his captors to destroy this nation."
So until someone in the MSM can point to any responsible member of "the right" who's purveying this garbage, perhaps they ought to give it a rest.