You are correct, unless Obama was born abroad. That’s because at that time the law for a parent abroad was that they had to have lived in the USA for at least 5 years after they had turned 14. That was basically to prevent children of 18 year olds serving in the military from being citizens. Obama’s mother was only 18 when she had him. Of course if he was born in Hawaii as he claims then that’s a different story.
His claim is more than a claim because the state has accepted his claim and issued him a birth certificate. So it matters not whether he was actually born in Hawaii or born in Kenya. Remember how in the Wizard of Oz how the Scarecrow wished he had a brain and the Wizard gave him a diploma?