You are correct with regards to detailed implementation of governance, which is best left to more temporal statutes. When it comes to delineating the limitations of federal authority, it is better to be explicit. The overarching doctrine with our constitution is that the federal government is one of limited powers - if there is no grant of power in the constitution, there is no federal authority. With state powers it is the opposite: if there is no prohibition on a state power (a power granted to a state by something other than the federal constitution, eg: in their own constitutions), the federal government cannot prevent the state government from exercising that power.
It has always been this way, look at Article I sections 8 through 10. Since the beginning, grants of federal powers and restrictions on state powers have been explicit.
The states which are a party to the federal constitution were so concerned about the possibility of federal overreach that they made this doctrine explicit, Amendment X (1791),
The powers not delegated to the United States by the Constitution, nor prohibited by it to the states, are reserved to the states respectively, or to the people.
Unlike the allegory of the children and the candy bar, which is a simple power-sharing agreement, the federal constitution creates a fiduciary to mediate disputes: the federal government. As such it is entirely appropriate to be explicit as to when each party must yield to the mediator - the last thing you and your brother want is to appoint me as a fiduciary only to see me eat the whole candy bar myself.
The Preamble to the federal constitution is not binding. Like all preambles, it acts as a statement of intent to the text which follows. That the rest of the constitution does not live up to its preamble, in modern times, only reinforces my conviction that we need more amendments.
I wish to re-emphasize that my legal opinions about the federal government do not necessarily reflect my ideals. While I believe the proper role of a national government includes maintaining an air force, I believe the U.S. Air Force is unconstitutional. (the constitution grants Congress limited powers to “raise and support Armies”, to “provide and maintain a Navy”, and to “make Rules for the Government and Regulation of the land and naval Forces”). Therefore the constitution is flawed and should be amended. How could it not be so? The Wright Brothers didn’t fly until 1903, while the Constitution was written in the eighteenth century.
~Max