Let me ask you a question: on what exactly do you base your assumption that Obama is a legitimate U.S. citizen?
Did you just take it for granted, assuming someone would have figured it out by now? Did you accept that phony looking "Certificate of Live Birth" his website posted? It has been thoroughly examined and summarily declared an obvious phony.
Now, you could dismiss what I just said. But instead, I urge you to look at the first website below. There are at least half a dozen obvious signs of tampering on that one document alone. (and very suspiciously, Obama's website substituted a much lower resolution version of the document, probably after realizing that someone could even analyze it by capturing the image on their own computer... which luckily this expert in document fraud and verification below did in time).
Did you really think this controversy is just some lighthearted whim by some whack jobs? Far from it, even Collin Powell has joined other black politicians like Alan Keyes in demanding that Obama produce a real birth certificate.
There is something very weird going on. It is well known that, during the primaries, Hillary sent her hencemen abroad to dig up dirt on Obama. Now he has chosen her for Secretary of State? Hmmm...
Additionally, it has been reported that Obama has spent $800,000 to avoid presenting a simple birth certificate. Why? He also used the pretext of his grandmother's death to whisk on down to the Hawaii records office and have his records sealed. Again, if there is nothing to hide, why?
What do we really know about Barack Hussein Obama? The only thing we do know is that with every new piece of information discloed, the less he looks like Presidential material. It is widely concluded in literary circles that Obama did NOT write "Dreams Of My Father". The style is very similar to that of a certain person Obama now claims he only knows "in passing" (despite the fact that Obama began his political career in his house): 1960s terrorist Bill Ayers.
Even if Obama produced some document that could not be proven a forgery, there are a couple huge obstacles towards proving his legitimate citizenship. His mother remarried an Indonesian man and they moved to Indonesia. She took Indonesian citizenship, meaning that "Barry Soetero" lost all claim to U.S. citizenship at that point. That is the law, according to the U.S. Naturalization Act of 1940.
I believe Obama was born in Kenya, and his mother raced back to Hawaii to get his birth recorded there (realizing her marriage to this Kenyan man would not work out). She then remarried, and took Indonesian citizenship. Hence, Barack, or Barry, or whatever he wants to call himself is not a legitimate U.S. citizen.