"To Ourselves and Out POSTERITY" might be the most important line. Who exactly were these blessings of Liberty for? For the whole planet, for all time, of all races and nations forever into perpetuity? Or for a specific people?
It's quite clear actually. America, and the identity and Rights of an American, are for the founding race of European stock alone, who similarly forged this nation and fought for it, and their descendants.
Real Americans don't have a hyphenated-American identity. We're just Americans.
