He can't, and you have hit the very heart of the matter. The BC stuff is interesting to follow, but it has completely overshadowed the fact that, according to Barack Obama himself, his father was not a U.S citizen, which means there is absolutely no way Mr. Obama can be considered a "natural born citizen" according to the intent of our Constitution.
The NBC clause is about allegiance to our country, rather than location of birth, and this commitment was expected to be preserved by requiring that a President would be born into solid allegiance to this country by two parents who were either born here themselves, or who naturalized and swore an oath the this country, renouncing their former allegiances.
Hope you've got some flame-proof attire... You're probably in for some heat :-)
Very nicely put!
Thank you!