A quick warning: the birthers among us do not accept that simple fact. They will argue that there is a category of born citizen that is not "natural born" citizen. You will cite decisions that plainly support your point, and they will slice the sentences and paragraphs into little pieces and reassemble them to mean something you won't recognize. At some point you will walk away shaking your head in disbelief, at which point they will declare that they have proven you wrong.
Just trying to save you some time. Engage for fun if you want, but don't expect to get anywhere.