The requirement that you must be a natural born US citizen goes back to when the Constitution was being written in 1787 (6 years after the War of Independence ended). The Americans had just finished a war with the British and did not want anybody born in another country to become their president. Basically a reaction to relatively current events at the time and their impact. If you know history, it makes sense. Now should it be changed since we're 230+ years in the future, yep.