Americans didn't always worship the Founding Fathers. The only one I hero worship is George Washington. It's difficult to overstate how much he influenced and shaped the country through his character alone. I've read many biographies of the man and the worst things people can say about him are his ambition, occasionally short temper, and reluctance to become overly familiar with anyone. He's the greatest American and probably one of the greatest men who was not a canonized saint to ever walk the earth.
As for the rest, the older I get the more convinced I am that the Anti-Federalists had their number all along.
The normative force of any law, including the Constitution, depends on the natural law. Any positive law that purports to contradict the natural law is unjust and we are under no obligation to obey; in fact, we have a moral obligation to disobey. Left-liberals dislike dogmas and clear distinctions, so they conceived the notion of a "living Constitution." The Constitution can change over time through the amendment process, but that's not quick enough. The meanings of the words can be changed to suit the needs of the present moment. There's only one thing that needs to be said about the concept of a living Constitution whose basic meaning changes over time. That term is a technical one from political science: bullshit.
Right-liberals - also known as conservatives - conceived the notion of Originalism or strict constructionism as a counter. Whatever you call it, it's essentially legal positivism. I'm more sympathetic to this idea but it's still an error. Positivism in religion is exemplified by the Protestant belief in Sola Scriptura. All meaning is confined to a closed text. In theory, the early Protestants thought this would lead Christianity back to the purity of the early Church. In practice, Sola Scriptura means the Bible means whatever the individual believer thinks it means which is why there are thousands of Protestant sects throughout the world.
Applied to the Constitution, far from confining all meaning to the text, it would mean the text means whatever judges and politicians want it to mean. Further, it provides cover for politicians and judges to willfully cooperate with evil or who are too cowardly to resist. It's possible, even likely, that the Supreme Court is going to discover a "right" to sodomite marriage in the Constitution this year, just as it discovered the "right" to abortion in Roe v. Wade. Chief Justice John Roberts, a Catholic, said in his confirmation hearings that Roe is the law of the land and that his personal beliefs would play no part in his legal decisions about abortion. In the future, I imagine all Supreme Court nominees will have to offer their pinch of incense to the legal reality of sodomite marriage (I say legal, but ontologically marriage cannot exist between two persons of the same sex.) Positivist legal theories are not exculpatory. You are formally cooperating with evil when you enforce evil laws. And don't even start with "I'm personally opposed, but…"
What conservatives seldom understand is that positivism is not the opposite of post-modernism. They're two sides of the same erroneous coin. Post-modernism was born from the realization that positivism is nonsense. The left-liberal, despairing of his project to turn man into God, declared that nothing had any stable meaning anymore. That road eventually leads to nihilism and madness. Both positivism and post-modernism are efforts to push the natural law outside the Overton Window and replace it with the Nietzschean superman's will to power. When the legal system is disconnected from the natural law, then all the little laws show up to fill in the gaps of day-to-day life. The Constitution and the Founding Fathers become our great Oracles, the answer to every possible question.
Americans are discouraged from thinking of themselves as a distinct people. The "blood and soil" theory of nationalism and ethnicity strikes American ears as weird and vaguely Nazi-ish. Instead, we base our identity on the ideas contained in the Declaration of Independence and the Constitution. If you believe in those principles, then you're just as American as the man whose ancestors were at Jamestown. And for that reason, many Americans have great difficulty accepting the notion that the Constitution might contain fatal weaknesses. Whatever flaws exist in the American system of governance are preemptively blamed on moral failings of the population. We have this great fear that if the Constitution is someday amended or reinterpreted to become something monstrous - such as guaranteeing the rights to abortion and sodomite marriage - then somehow America itself will become an illegitimate nation. Our identities are closely bound to our specific system of governance, and if that system breaks down and fails, then who are we?
Nonsense. A sinner doesn't become non-human because he has sinned. He has an obligation to repent, confess, and amend his life. Likewise, if America exalts certain evil practices, she doesn't cease to become a nation. She gains an obligation to repent.