Originalism and post-modernism

I posted this to my status at Facebook but decided it deserved a wider audience. At the same time, I really don't want to deal too much with the liberal commentators at W4, so I'm compromising by posting it here. Which probably means it won't actually have a wider audience. Anyway, this is what I said:

Does it ever occur to the people who teach in U.S. law schools that there is great moral hazard in teaching, even requiring, the most intelligent young people in the country, its future leaders, to regard the reality governing all the citizens of the most powerful nation in the world as literally created by the will of nine human beings?

Further ruminations on the subject: I see people talking about whether the individual mandate in Obamacare is constitutional, and what I realize is that when lawyers talk about this, they are simply making a prediction. What will SCOTUS rule? Ultimately, that's going to be the question. Lawyers are taught that the Constitution means what the Supreme Court says it means. The Supreme Court, in other words, creates the meaning of the Constitution in an on-going act of pure will and power. So if the Supreme Court rules that the federal government has all powers not expressly forbidden to it in the Constitution (which is directly contrary to the 10th amendment as well as to the entire assumption of enumerated powers that makes the Constitution necessary in the first place and that governs its structure of laying out the powers of the different branches of the federal government), why, then, that's what the Constitution means. If they somehow descry this grant of plenary power over every individual in the country to make that individual do what Congress wishes hidden somewhere in the 16th amendment (that's the income tax amendment), why, then, that's what the 16th amendment means.

Now, if that doesn't bother you, as an American, it should. Yet that's what the law schools have been teaching for decades. The Constitution has no external meaning. It means what the courts rule.

I don't care if you regard yourself as a natural law theorist on con-law. I don't care if you think Antonin Scalia is a "positivist" and this is a bad thing. I ask you to think: Isn't there something very, very wrong with a purely postmodern view of the very constituting document of our country according to which it has no stable meaning? Isn't there something very, very wrong with a situation where the question, "Is it true that the individual mandate is constitutional?" has nothing to do with a stable meaning of the Constitution but is merely a question of prediction about what nine black-robed rulers will say in a few months?