We the People of the United States, in Order to form a more perfect Union... and secure the Blessings of Liberty to ourselves and our Posterity, do ordain and establish this Constitution for the United States of America.
Whom else was the Constitution established to secure, if not the citizen People and their citizen children?
-PJ
OK, I'm not sure I follow your connection. How does that say anything about what a natural born citizen is? It says they are writing a Constitution for themselves and their children - but it doesn't say "only our children and ourselves". In fact, the Constitution explicitly states how we can add more people to Ourselves corporately!