Thew issue is not citizenship. Obama is a citizen and has a passport to prove it. The issue is whether he is natural born using
jus solis or
jus sanguinis. Since his father is not a US citizen, he is not eligible to be a natural born citizen if born abroad.
Birth Abroad to One Citizen and One Alien Parent in Wedlock: A child born abroad to one U.S. citizen parent and one alien parent acquires U.S. citizenship at birth under Section 301(g) INA provided the citizen parent was physically present in the U.S. for the time period required by the law applicable at the time of the child's birth. (For birth on or after November 14, 1986, a period of five years physical presence, two after the age of fourteen is required. For birth between December 24, 1952 and November 13, 1986, a period of ten years, five after the age of fourteen are required for physical presence in the U.S. to transmit U.S. citizenship to the child.
Obama's mother was 18 when he was born in 1961. So the only question is whether Obama was born in the US. He could clear that up immediately by producing his live birth certificate showing the attending physician, name of hospital, etc. like McCain has done. I am not a conspiracy nut, but I do find it odd why Obama is fighting the Berg and other suits in court when he can clear things up very easily. The question then becomes what is he hiding?