What would happen if a constitutional amendment were passed that forbade the passing of any more amendments? Would it be able to achieve that, or would something get in the way? I realize this would be practically impossible to pass, in addition to being a terrible idea. This is purely hypothetical.
Well, we could then start looking for a way to unfreeze Hell.
Theoretically, a constitutional amendment can make the constitution say anything, however, such an amendment would probably be unconstitutional even if it was passed in accordance with the constitution.
It is certainly the case that the SCOTUS would probably find that, notwithstanding there is a mechanism for such a change, it is actually beyond the power of Congress to make such a change. It is possible that a Constitutional Convention that proposed such a change would on the face of it be less problematic than a Congress initiated one but I still think that SCOTUS would strike it down as acting beyond its power.
That is because there are certain things within the Constitution that are so fundamental to its existence and operation that they cannot be removed. Other things that would probably fail in this way are any amendment to abolish the POTUS, the SCOTUS or the Congress.
As an analogy, the English courts have held that Parliament has supreme sovereign authority in the United Kingdom. They can literally do anything without fetters of precedent, constitutionality or human rights. Except for two things. They cannot abolish the institution of Parliament and they cannot bind the supremacy of future Parliaments to undo what they do.
Dale M's answer is not supported at all by history, or any mode of constitutional interpretation. I also don't find it likely. I'd say that if a duly ratified amendment said as much, that would be the law. It is certainly correct that the court could try to narrow the meaning. It's also possible to simply not follow the Constitution (as we do with state immunity and the 11th amendment). But to assume that would be done here is just speculating blindly. Of course, this question doesn't warrant much more attention than blind speculation, so my comment is not a very offensive accusation.
As a few counter points, we have radically change the form of our government many times within the current constitution. Reconstruction, The New Deal and so on, all represented huge changes. Most importantly, the 17th amendment can easily be viewed as more radical than the question's proposed amendment. It completely flipped the political system upside down, orienting power in the people and the federal government, and treating the states as some weird intermediary: but we now see it as a relatively boring enactment.
Certainly we could come to see the formal abolishment of the amendment process similarly, especially if it were (which it would need to be) accompanied with a new found comfort with non-textual interpretation to effectively "amend" through interpretation, i.e. If the textualists lost badly this amendment would seem like a relatively natural way of announcing their demise. Remember that Scalia's whole point, is that strict originalism (not saying he was actually so strict himself) would democratize by forcing change through the amendment process. If we rejected that notion (as deceptive, for example) we could (as in its not completely ridiculous to imagine) announce that rejection with the proposed amendment.
In this purely hypothetical scenario, such an amendment would effectively "lock" the constitution into a static document forever.
It's hard to excerpt specific highlights from from Article 5 because the whole thing is a single, run-on sentence. BUT, @Dale's answer is fundamentally incorrect.
Here is the text:
The Congress, whenever two thirds of both Houses shall deem it necessary, shall propose Amendments to this Constitution, or, on the Application of the Legislatures of two thirds of the several States, shall call a Convention for proposing Amendments, which, in either Case, shall be valid to all Intents and Purposes, as part of this Constitution, when ratified by the Legislatures of three fourths of the several States, or by Conventions in three fourths thereof, as the one or the other Mode of Ratification may be proposed by the Congress; Provided that no Amendment which may be made prior to the Year One thousand eight hundred and eight shall in any Manner affect the first and fourth Clauses in the Ninth Section of the first Article; and that no State, without its Consent, shall be deprived of its equal Suffrage in the Senate.
There are several observations that should be noted here:
- A constitutional amendment is "...valid to all Intents and Purposes, as part of this Constitution". In other words, it becomes a part of the constitution itself. The Supreme Court cannot rule unconstitutional something that is in the constitution. Indeed, if such an amendment were to pass, the only thing that could modify or repeal it is another constitutional amendment -- which cannot happen because a further amendment would then be unconstitutional on its face.
- The executive and judicial branches of the government are conspicuously absent from the amendment process. Ratification of amendments is exclusively a legislative action -- that means two thirds of both houses of Congress and 3/4ths of the state legislatures. The only power of judicial review the Supreme Court could have would be procedural in nature (i.e. was the process in Article V followed correctly?), and the President would not be able to veto it.
- The only subject that is off-limits in the amendment process is equal suffrage in the Senate. I won't elaborate on this because it's not relevant to the question. I only mention it because this would be one of those procedural things SCOTUS could weigh in on if such an amendment were passed.
The Constitution vests pretty much absolute power with the states and the people. Strictly from a constitutional perspective, the people it serves are free to completely destroy it or undermine it as much as they want, as long as the proper procedure for doing so is followed. It offers no protections whatsoever for the event that the American people collectively lose their minds.