No he wasn't. If a billion people say 2 + 2 = 5 doesn't make the equation correct. Obama the putative president of the United States, as the Commander in Chief, is the source of all military authority. If he occupies that office illegally, he has NO authority to give lawful orders as Commander in Chief. He derives his total authority and much of his legitimacy from the US Constitution.
The problem that I have with this assertion is that having been elected and sworn in without any challenge to his legitimacy, the only remedy now available is the impeachment process. Those who claim that discovery of his illegitimacy will render his entire Presidency moot are ignoring the Constitutional and legal realities. The Courts can't act, the FBI can't act, Barney Fife can't act. Only the Congress can act on evidence that he is ineligible for the office and that will never happen. Its not a perfect world.