Where's Pres. Obama's Birth Certificate?

Why won't Pres. Obama show us his birth certificate? Does he have one? Was he born in the United States? If he was not born in the United States then he does not qualify to be our President. He could put this all to rest if he would just hand it over. The fact that he has not revealed it makes me wonder if he is not an American citizen. Is that the impression you get? There is a petition at worldnetdaily.com that I would suggest that you sign. This is important for our country and our future. Our Constitution says that no one can be sworn in as President if they are not a natural born citizen. Obama could make this all go away if he would release his birth certificate.