IMHO, that is the one flaw...no ‘teeth’. But, I suspect, the Founders thought we’d be re-fighting for our Independence WAY before today for all the Rights and Liberty we have lost.
"A Republic, if you can keep it." - Ben Franklin
They knew the flaw, but its a flaw that cannot be fixed with written words. The only fix is for those oppressed to make the consequences so unpleasant that the majority will respect their rights.
The 2A was intended to make that feasible. Note that they were also against a standing army.