What would happen if Obama really was born outside of the U.S.?

If Obama is ineligible, then he would have to be impeached and removed from office. This is because he was elected by the Electoral College, the results confirmed by Congress, and sworn in -- all according to the Constitution. He IS the sitting president until tried and removed by Congress. If Obama is removed from office, Biden is president.

All laws, appointments, and executive orders made by Obama STAND. Look up the "De Facto Officer doctrine", a well-established legal concept. If an officer (president is an officer of the US) is later found to be fraudulent, his official acts do not get rescinded. They were made by the OFFICE not the person, and the office is legitimate even if the person holding it wasn't. Thus if Obama was found to be ineligible, nothing he did would be overturned. The Supreme Court has said:

"The de facto officer doctrine confers validity upon acts performed by a person acting under the color of official title even though it is later discovered that the legality of that person's appointment or election to office is deficient." "The de facto doctrine springs from the fear of the chaos that would result from multiple and repetitious suits challenging every action taken by every official whose claim to office could be open to question, and seeks to protect the public by insuring the orderly functioning of the government despite technical defects in title to office."

Then he has been breaking the law for 4 years

then he would'nt have been president, because you have to be a american born to be the president of United States

He probably was.. and nothing has happened so far because no one cares enough to challenge him on it.

If he is illegal tho.. he should be jailed for life!

it would be a mess

are you talking about biden when he is not trashing obama like he did yesterday