The problems with Consitutional Fundmentalism are rather obvious. Those who believe in this political theory, unlike the founding fathers, must believe that the 1789 consitution was perfect AND perfectly obvious, too.
That belief system presumes that the words in that document are not subject to interpretation. They are obviously wrong, That is why the founding fathers created the SCOTUS. To interpret what the words on the paper actually mean and how our government is meant to carry out the principles in that document.
The other problem ought to be obvious, too. The 1789 constiution sanctioned slavery with the 3/5th clause and it failed to grant the franchise to women, too.
So the next time sombebody tells you that they believe in the literal interpretation of the original US constitution, ask them if they also believe that we need to literally follow the 3/5th clause.
"Representative and direct Taxes shall be apportioned among the several
States which may be included within this Union, according to their
respective Numbers, which shall be determined by adding to the whole
Number of free Persons, including those bound to Service for a Term of
Years, and excluding Indians not taxed, three-fifths of all other Persons."