There's a practical lesson here: in contentious areas like politics, having a standard everyone agrees on—even if they don't agree on interpretation—is valuable

There's a practical lesson here: in contentious areas like politics, having a standard everyone agrees on—even if they don't agree on interpretation—is valuable in and of itself. The Constitution and its surrounding documents are foundational simply because they're foundational, not because they are the final word on political philosophy or practical governance. The Constitution just has to be good enough to supply a floor for the quality of a government that has any pretense of following it and, for the past few hundred years, it's done the job well enough to survive despite some fundamental failings. And in practice, whatever anybody says, the interpretation of the Constitution has evolved massively over the country's history, even along supposedly originalist views. The most important ideas in the Constitution—say, the First Amendment—are intentionally under-specified; the full meaning of the First Amendment is not in its 45 words but in centuries of legal scholarship and judicial precedent. While the Amendment itself has a couple of centuries under its belt, its practical manifestation in American legal practice is at least as sophisticated and modern as anywhere else.