A good rule of thumb I’ve discovered is that critics who claim Rep. Ron Paul doesn’t understand the Constitution are themselves the ones whose knowledge is deficient.

For example, Scott McKeag, a teacher in the Iowa City School District, came down hard on the congressman in these pages for denying that the federal government has a role in education according to the Constitution. The congressman further believes that education is better managed by states, localities, and parents.

McKeag cites the Constitution’s “necessary and proper” clause to justify the federal Department of Education, which opened its doors in 1980.

Let’s tick off the problems with this howler.

First, Alexander Hamilton noted in Federalist No. 33 that the necessary and proper clause was inserted merely for clarification and did not augment federal power at all. He even said the Constitution would be exactly the same if that clause were “entirely obliterated.” Appealing to the clause to carry the burden of justifying federal involvement in education — which is nowhere mentioned in the Constitution — is asking it to do much heavier lifting than even Hamilton, the broadest of constitutional constructionists, thought it could bear.

Second, George Nicholas, future attorney general of Kentucky, told the Virginia ratifying convention (and remember, according to James Madison, it is to the ratifying conventions that we turn for constitutional interpretation) that the clause “only enables it [Congress] to carry into execution the powers given to it, but gives it no additional power.” Many other statements to this effect can be found in the documentary records of the ratifying conventions.

In other words, citing this clause for authority to establish a Department of Education only begs the question, since McKeag has not first established education as one of “the powers given to it.”

Third, in numerous state ratifying conventions, the people were assured the federal government would have only the powers “expressly delegated” to it. Power over education is obviously not expressly delegated.

Fourth, Thomas Jefferson explained in 1791 that “necessary and proper” had to mean really necessary, as opposed to merely convenient, in carrying out the enumerated powers if the clause were not to swallow up the whole Constitution and defeat its very purpose. Because education is nowhere listed among the enumerated powers, it wouldn’t survive even the first stage of Jefferson’s test.

McKeag only makes things worse when he appeals to Jefferson: “President Thomas Jefferson, the author of the Declaration of Independence, championed this idea from his time in the Virginia Legislature.”

Ouch. Here’s what Jefferson actually said: “An amendment to our Constitution must here come in aid of the public education.”

Got that? An amendment to our Constitution. That means federal involvement in education is unconstitutional given the text of the document as it stands. In other words, Jefferson held precisely the view that Ron Paul holds today.

McKeag has no better luck when he tries to claim Madison. Madison warned people in 1792 that if they interpreted the general welfare clause too broadly, we’d wind up with the federal government taking “into its own hands the education of children,” an outcome he considered absurd. Ouch again, Mr. McKeag.

The rest of the article argues from the precedent, “Hey, lots of politicians have thought the people were too stupid to run their own schools and needed to be taxed for the privilege of being bossed around by their Washington betters.” Maybe so, but that doesn’t answer the question: Is it constitutional?

Before filling the heads of Iowan children with any more nonsense, Scott McKeag might consider leaving Ron Paul alone and spending a teensy bit more time reading.

Thomas E. Woods Jr., who holds a Ph.D. in history from Columbia University, is a New York Times bestselling author of 11 books.