The White House is warning of a new Great Depression while invoking a statute that contributed to the original.

W hite House officials have repeatedly said that if the courts strike down the president’s tariffs imposed supposedly on the authority of the International Economic Emergency Powers Act (IEEPA), the president’s tariff policy would be neutered. This is because alternative statutory sources of presidential tariff authority are much more limited. However, officials are likely to change their tune if and when the Supreme Court agrees with the two lower courts that have ruled that the President’s IEEPA tariffs exceed his power. One alternative the administration apparently is considering turning to is the discredited and effectively repealed Smoot–Hawley Tariff Act, which turned an economic downturn into a decade-long catastrophe.

The Supreme Court is currently considering whether to take up the case of the president’s IEEPA-based tariffs. Leading into Labor Day weekend, the Federal Circuit Court of Appeals, affirming the decision of the U.S. Court of International Trade, found that the IEEPA does not empower the president to impose “tariffs of unlimited duration on imports of nearly all goods from nearly every country with which the United States conducts trade.” Explaining its decision, the Federal Circuit pointed out that “every” statute that explicitly grants the president some authority to modify tariff rates “includes well-defined procedural and substantive limitations” on that power. White House officials apparently agree.

In an August 11 letter to the Federal Circuit, the president’s lawyers wrote that “tariff authorities [other than IEEPA] that the President could potentially use are short-term [and] not nearly as powerful.” In another letter to the court, filed just hours before its decision on August 29, Secretary of Commerce Howard Lutnick warned the court that “without the viability of IEEPA tariffs, the United States would be weakened and lose the essential tool to address this national emergency most efficiently” (emphasis added). And, in a recent interview, Treasury Secretary Scott Bessent said that although “there are lots of other [tariff] authorities that can be used,” they are “not as efficient, not as powerful,” as IEEPA.

According to Bessent, Trump’s “Plan B” involves attempting to resurrect his tariff agenda by using an obscure clause of this 95-year-old law known as Section 338. Fearing foreign retaliation against its own protective tariff schedule under Smoot–Hawley, Congress authorized the president to impose tariffs of up to 50 percent on any country that deploys discriminatory trade practices against the United States. Section 338 did not work as intended, as Smoot–Hawley triggered a catastrophic global trade war that brought international commerce to a halt, destroyed the U.S. export market, and thrust us deeper into the Great Depression. Its language remains on the books as a vestigial relic of this notorious law, although its functions have been superseded by later tariff law revisions that imposed more restrictions on the president’s authority.

While the stock market collapse in 1929 marked the beginning of the Depression, it received its “Great” moniker thanks to interventionist economic policies and government mismanagement of the crisis. Economic historians usually point to three such blunders: an artificially tight monetary policy owing to Federal Reserve mismanagement, a series of income tax hikes in a failed attempt to balance the federal budget, and the protectionist Smoot–Hawley Tariff Act of 1930.

This third blunder originated as a relief measure intended to insulate American producers from turmoil on international markets and “stimulate” them with the benefit of tariff protection. Instead, it triggered a lobbyist-driven free-for-all as industries clamored for favorable rates and special interest groups bribed their way onto the tariff schedule. Our major trading partners retaliated by targeting American exports, which included the already beleaguered agricultural sector. U.S. exports dropped by 61 percent between 1930 and 1933, showing what economists had long predicted: attempts to insulate the country from foreign import competition affect the entire economy and ultimately hurt domestic industries as well.

With the collapse of global trade in the wake of Smoot–Hawley, Section 338 was never used. Instead, Congress realized its error and, in 1934, passed the Reciprocal Trade Agreements Act. This measure authorized the president to lower tariff rates by up to 50 percent by negotiating reciprocal concessions from other countries, subject to congressional approval. Later measures, including the Trade Expansion Act of 1962, added language clarifying and detailing how tariff and nontariff barriers enacted by a trading partner might “burden United States commerce” and laying out the specific procedures by which the president could “investigate” such potential discriminatory action and apply countermeasures. In legal terminology, these and other more recent statutes “superseded” Section 338 of Smoot–Hawley by overriding its contemplated presidential tariff power with stricter conditions and more precise definitions. Until the Trump administration’s novel legal theories came along, Section 338 was long considered a dead letter — buried in shame with the rest of Smoot–Hawley’s economic legacy.

President Trump likes tariffs and has for a long time, advocating them as early as the 1980s. To him and his advisers, IEEPA is a tool for implementing his preferred policy. If that tool breaks, he’ll look for another. One might have hoped that Smoot–Hawley’s inauspicious history would preclude the White House from turning to it, but apparently that’s not the case.

The president’s desire to implement tariffs is detached from his legal authority to do so as well as from the harm they are causing. The American economy is already slowing, and our allies are deepening their commercial relationships with our enemies. Whether imposed under IEEPA, Smoot–Hawley, or some other statute, tariffs will continue to hurt Americans until Congress or the courts intervene and enforce constitutional limitations on presidential power.

Phillip W. Magness is a senior fellow at the Independent Institute and the David J. Theroux Chair in Political Economy. Marc Wheat is the general counsel for Advancing American Freedom.