“Ludicrous.” That is how Gina McCarthy, the federal government’s top environmental regulator, described the concerns of farmers and ranchers about a new rule that would “clarify” the reach of federal power. Her flippancy recalls then-House Speaker Nancy Pelosi’s “Are you serious? Are you serious?” response to a reporter’s question about whether the Constitution actually grants Congress power to impose a health insurance mandate.

McCarthy became Administrator of the Environmental Protection Agency last year after serving in the number-two position there since 2009. Before moving to Washington, D.C., she was a longtime regulatory bureaucrat in Connecticut and Massachusetts. The EPA is a powerful federal agency — there is even an EPA SWAT team — that enforces federal environmental laws. One of those laws is the Clean Water Act.

Like many pieces of modern legislation, the Clean Water Act starts with vague, aspirational goals and then devolves into thousands of words of regulatory jargon. Not only enforcement, but many details, are left to Executive Branch agencies, like the EPA. Agency staff have every incentive to interpret such legislation expansively in order to increase their own power and their agency’s budget.

In 2001, the U.S. Supreme Court began to push back against the EPA’s expansive interpretation of the Clean Water Act. The fundamental question at issue is the extent of federal power. Ultimately, all law enforcement, regulation, and statutes must, at the federal level, come from power granted to the federal government in the Constitution. Beyond those boundaries is lawlessness.

Congress and the courts have rationalized the Clean Water Act (and many other federal acts) as resting on the grant of power in Article I, Section 8, “to regulate Commerce with foreign Nations, and among the several States, and with the Indian Tribes.”

At best, this is a stretch. The Clean Water Act asserts federal power over “navigable waters,” that is, waters that could be used for commerce. The EPA, however, has claimed authority to regulate streams and even dry streambeds that might eventually flow into “navigable waters.” As the Washington Legal Foundation pointed out in a Supreme Court brief, the EPA’s legal theory rests on the same premise as the movie Finding Nemo: “all drains lead to the ocean.”

The most obvious flaw in any such theory is that the federal Constitution was written in order to limit federal power. It was only ratified based on the understanding that it did, in fact, place real limits on that power. James Madison, writing about the proposed Constitution in The Federalist, explained “its jurisdiction extends to certain enumerated subjects only, and leaves to the several States a residuary and inviolable sovereignty over all other objects.”

The proposed EPA rule drawing criticism from farmers, ranchers, and others claims to “clarify” those waters subject to regulation under the Clean Water Act. Yet it includes phrases like “case-specific basis” and “significant nexus” that will be left to EPA bureaucrats and enforcement officials to later interpret. It also explicitly extends federal power to nearly every watercourse that eventually leads to a navigable water, a long-accepted but still dubious claim.

The concern of farmers and ranchers is whether federal regulators will blindly or intentionally interfere with their families’ livelihoods and, consequently, with food production. While not usually put in constitutional terms, the conflict gets at the purpose for the constitutional system of limited federal powers. The Constitution was not written simply to place arbitrary shackles on Congress or the President or his executive agencies. The purpose was to protect local decision making and thus to protect local communities from far-away bureaucrats.

McCarthy, from the most urban region in the United States and now a resident of Washington, D.C., is hardly in the best position to make decisions about cattle ranching or drinking water for people in Oklahoma. And the state of Oklahoma, like every other state, has public officials tasked with thinking about these very same things. (After decades of federal overreach and poor civics teaching, this point is often lost, even on local journalists who should know better — Austin’s KVUE reported that only the EPA can stop people dumping pollution into Texas creeks, in ignorance of the state’s power and its own environmental agency.)

The limits on federal power and the system of states known as federalism exist in the Constitution to protect people. They are there to minimize the impact of distant, centralized power — so prone to hubris — on diverse local communities spread across a vast and variegated geography. By attacking the concerns of Midwestern farmers and ranchers, McCarthy provides a cautionary reminder of why the American Founders were, and Americans today should remain, skeptical of federal power.