Everybody knows the regular case for Impeachment by now: the war, Katrina, spying, torture, signing statements, Constitutional responsibility, blah, blah, blah, blah, blah. That boat has already left the station, and the train it's on has sailed.
Here's the other case, underlying the regular case, which means it's lying under the train and the boat.
Article I : High Crimes
There is a prima facie case, which is also a priori and ad nauseam, that the president had to have been high when he committed all those crimes.
Article II: And Misdemeanors
A misdemeanor is like being drunk and getting into a bar fight. Now we know that the President gave up drinking sometime in his forties, when Jesus told him to. So I'm not saying he's been drinking, although that would explain a lot. But there's enormous circumstantial evidence that he got into a bar fight, which is the only possible explanation for why he got us into this stupid war. Other than the oil thing, which I've never believed, at least not after they realized they couldn't call it Operation Iraqi Liberation because of the unfortunate acronym. So it had to be a bar fight, where probably a little accountant who wore thick glasses kicked his ass, and so he had to start this war to show how totally manly he actually was in spite of having his ass kicked by an accountant. QED. And since this is an UAFZ (Unexplained Acronym-Free Zone) I'll give you the Latin: Quod Erectum Demonstrandum.
Article III: Constitutional Disqualification
Article Something, Subsection Whatever states that to be president a person must be 1) at least 35 years old, 2) born in this country, Ahhnold, and 3) smart enough to pour piss out of a boot if the directions are clearly printed on the heel. Our Founding Fathers were realists, so they set the Constitutional Bar very, very low. But this president, approaching that bar way too fast, ran straight into it, and it hit him right between the eyes.
Article IV: The Other Constitutional Thing
Also, the Codicil to Article Something located Somewhere, specifically states that anybody who thinks he was elected by God (not the people of the United States) and/or claims to get advice and direction from God must be removed immediately from office by means of a large hook, like they used in Vaudeville. We could also use a gong.
So, sorry, but he can't be president anymore.