You are exactly right, tonnyb. I'd placed a commented showing my analysis for why bigotry can be the ONLY explanation for the right-wing 'birther' movement. I repeat it here:

The 'Birthers' question whether President Obama was born in one of the 50 states, yet they find no problem with the fact that John McCain definitely wasn't born in any U.S. state. There's no dispute about this fact. McCain was, of course, born somewhere in the Panama Canal Zone, although exactly where in the zone still is the subject of some dispute. Was McCain born in a civilian hospital, or was he born on the Coco Solo U.S. military base there? The fact is, even that detail doesn't truly matter. Here's what the U.S. Department of State's manual on U.S. citizenship says regarding the effect of being born on U.S. military base situated in a foreign land, according to an excerpt reported in a Washington Post article:

"Despite widespread popular belief, U.S. military installations abroad and U.S. diplomatic or consular facilities are not part of the United States within the meaning of the 14th Amendment. A child born on the premises of such a facility is not subject to the jurisdiction of the United States and does not acquire U.S. citizenship by reason of birth."

Which means that the only way McCain could be construed to be a natural born citizen is on the basis of one or both of his parents being a U.S. citizen. There is no dispute that Obama's mother was a U.S. citizen at the time of his birth, so, at the very least, Obama is as eligible as John McCain is to be POTUS. Of course, The Dept. of State doesn't interpret the U.S. Constitution, the Supreme Court does. Since the SCOTUS has never, to my knowledge, determined a Constitutional definition of, "natural born", there is NO BASIS for anyone to claim that Obama is not eligible, while, somehow, McCain is.

Which leads us to the REAL reasons the Birthers have their panties in such a wad. President Barack Hussein Obama has brown skin and an Arabic sounding middle name. It's ethnic bigotry, pure and simple. That's the all of it. For, there have been other Democratic presidents, but no one disputed their eligibility, so it's not because of that. There have been more liberal presidents than Obama, so it's not that either.

Most tellingly, it is NOT over whether Obama was or wasn't born in one of the 50 U.S. states, because John McCain absolutely was not born in one. So, what else distinghuises Obama to produce this level of, "not-one-of-us", type vitriol? What explanation is left, beside bigotry? Such extreme racial bigotry toward a man who is half white. They must only see the black half when they look at him.