I don't think any requirement alone could completely safeguard us against those who might use the office to harm the United States. The birther-supported "two citizen parents" definition certainly doesn't.
Your post makes no sense. If the NBC requirement of the Constitution was inserted to insure the POTUS would have two citizen parents, then it most assuredly precludes a foreign enemy of the US fathering our president. If you can’t see that, you’re being willfully blind.
Or else you have construed NBC as a safeguard against discrimination. The Founders, fearing we might be prejudiced against foreigners who want to destroy our Republic, inserted it to mandate that any foreigner, however hostile to the US and bent on our destruction, should have his right to father our president enshrined forever in the Constitution.
Get real.