I think its an amazing coincidence that both of the candidates for president in the last election had serious questions raised about their American citizenship. To be president, the Constitution requires that a candidate be a "natural born citizen", but doesn't strictly define what it means to be 'naturally born'. We might interpret it to mean that a person should be born within the boundaries of the US (but what about incorporated territories or military bases?), be born to citizen parents (but what if you're born on foreign soil? or if only one parent is a citizen?), or perhaps it disqualifies any baby born by cesarean section? The supreme court has never settled the issue, but there have been many cases arguing the various merits of each condition over the years.
Neither of the candidates actually met the conditions for 'naturally born' citizenship in any clear cut way. McCain was born to American parents but in a Panamanian hospital which was outside of the then US administered canal zone. In 1937, American citizenship was conferred on those born in the canal zone retroactively, but a retroactive citizenship isn't very clearly meeting the criteria for 'naturally born' as regards location and McCain wasn't born in the zone anyway. Obama was born in Honolulu, HI (an American state for those of you not so up on your geography) so he clearly met the location standard, but to an American and a Brit (although we always hear his father referred to as being Kenyan, Kenya was a colony of Britain at the time), so by the parentage measure he falls short.
Another odd coincidence was the Manchurian candidate claims against McCain (suggesting that after he was elected the Koreans would call him up on the red phone, say a few key words, and he'd be acting on their behalf just as they had planned back in the torture sessions); and how these kinds of claims contrasted with the fear mongering about Obama as a secret Muslim who might immediately gas up air force one for a strategic one way trip into the capital building as soon as he took office.
Its sad that there is still an argument over Obama's birth certificate when it has been so clearly established to be valid. Sadder still that the 'Birthers' are willing to waste so much time on idiotic claims when they could be helping to solve real problems. But it would be nice if we could actually define 'naturally born' in a clear cut way for the future.