[MosesKnows]

Upon what rationale do you base these assertions?

I base my assertions on the notion that only Congress can legislate.

The 13th, 14th, and 15th Amendments and the 18th, 19th, 23th, 24th, and 26th Amendments have this in common.

Congress shall have the power to enforce this article by appropriate legislation.

[Jim W N]

As long as the amendments were processed and duly ratified per constitutional requirements, then they are valid amendments and per the Supremacy Clause (US Const., Art. VI, Cl. 2) they are part of the Supreme Law of the Land.

I don’t see a problem with Congress being tasked to enforce these amendments. It’s asking Congress to enforce constitutional law.

[MortMan]

These amendments are not legislation, and they are law. The amendments modify the constitution to state what is allowed or not allowed. The clause you site about congress having power to enforce means that congress is enabled to build a legislative structure around the amendment “law” to ensure it is properly enforced.

Consider the first amendment. It starts with “Congress shall make no law”. Using the logic you present, the first wouldn’t be “law”, either. IMHO.

[fruser1]

Congress shall have the power to enforce this article by appropriate legislation.

Perhaps the more appropriate question is "Why do these amendments have this clause and the others do not?".