Article I, Section 5: "Each House may determine the rules of its proceedings..." would seem to cover it.

But, yes, you're right: Any subsequent law will generally obviate any previous law that it's in conflict with. Legislatures can't bind their successors with mere legislation. On the other hand, these kind of laws sometimes have their desired effect. Gramm-Rudmann-Hollings forced several Congresses into budget cuts because they had been so public in touting the bill. Ultimately, it died when it became untenable but it had its impact.

Suppose this were to pass into law. What exactly do you suppose would happen if and when Congress passed a law that did not include said statement? Would it not be deemed law even though it met all the criteria for law as described in the Constitution?

I think you stopped reading to soon. Its not just all laws "necessary and proper", but "necessary and proper for carrying into execution the foregoing powers".

I suspect that in practice this would quickly devolve into an exercise in boilerplate, but it shouldn't do any harm and might do some good. It is also the kind of legislation that "looks good" for the minority to put forward. If they majority kills it in committee (most likely), they can campaign against the majority for being against something that appeals to their base and a sizable center. If it passes, it isn't likely to bite them in the butt.

I seem to remember a controversy on whether the common defense power could be used to justify the congress saying how many children people should have. It went something like you need an army for the common defense. To have an army, you need soldiers. So stating each woman should have a minimum of X children is merely ensuring that enough soldiers will be available. At least something like this would make them state their logic on how this is somehow the business of congress to get involved.

For those on the left, imagine the Terry Schiavo case playing out with this requirement.

The president is given the power as commander-in-chief, to make various appointments, to demand answers from department heads, and to negotiate treaties. He's also given, though, what some (including George Washington) say is a blanket authority through its opening phrase, "The executive Power shall be vested in a President of the United States of America."

FindLaw has a superb and detailed discussion.

Congressman John Shadegg, who I wrote about here and here during last year’s race to replace Dick Armey as House Majority Leacder, has proposed an interesting new bill called the Enumerated Powers Act:
Yesterday, Congressman John Shadegg reintrod...

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