This isnt an unreasonable take on the purpose of the second ammendment, but where it falls down for me is the fact that it assumes the founders never accounted for what would happen if the country did create a professional army. Do you really believe that these men, who had just overthrown the shackles of tyrannical government, didn't consider that their government could become the same? If they really didn't want a national army I think that would have been included in the bill of rights.
But think your gun control stance is pretty pragmatic.