Donald Trump cancels appearance on Letterman show after Letterman points out that denying the President's citizenship "has the appearance of racism". Given that in an actual political campaign he would be accused of that and more, I think it's official: Mr. Trump is too thin-skinned to be President.
Here is Mr. Trump explaining that he's not a racist, it's all those people claiming he's a racist who are racist:
Gosh, all those tea party types sure are defensive about racism, aren't they? Alrighty, then!
-- Badtux the Snarky Penguin