Bamboozled: What made anyone think the Trump tariffs were legal?

The American people deserve an explanation on how the president of the United States on April 2 last year announced the largest tariff package in modern history with no action by Congress. It is not the province of the president to set tariffs. This is entirely within Congress's power. It is true that the Congress has delegated the power to the president to use tariffs for certain limited purposes, but very selectively, and hedged with strict conditions.

The US Constitution is quite clear that tariffs are entirely Congress’s prerogative. How could what Trump did happen? How could it even be a matter for litigation to prove the point that it was unauthorized? Presidents have proposed tariff legislation, they have signed tariff bills the Congress has passed, and they have administered some tariffs selectively under delegated authority. They have never imposed a single tariff, whether on steel, semiconductors, or peanut butter, without first getting a grant of authority from Congress. Not in any one’s wild imagination (saving the current president) could a president impose across-the-board tariffs against all products from all countries, on any authority said to have been granted.

There are reasons for this debacle. It comes from a complete misreading of the US law and history. In normal times, it would be worth a serious congressional investigation into why this happened. That will have to await the Congress reestablishing itself as a co-equal branch of government.

What happened? The president declared an emergency last April. Congress, the American people at large, and the countries with which we trade, were caught completely off guard, even though President-elect Trump had repeatedly said that he would impose massive tariffs.

As president, Trump declared an “emergency.” Everyone knew there really wasn’t one, the kind for which it would make sense to invoke a sort of martial law for trade. But “emergency” is a very imprecise word. The facts: Nothing out of the ordinary had occurred. Perhaps US trade deficits had begun to add up. But there had been no single shocking event, no calamitous fall in the dollar’s exchange rate. Interest rates were stable. It was just another year. The economy was growing. But there was a law on the books, pretty much the same since World War I, allowing the regulation of trade in an emergency. With the word “emergency” nowhere defined, presidents had gotten used to declaring emergencies all too often, some 77 of them even before Trump returned to office. The statute, the International Emergency Economic Powers Act (IEEPA), was used to impose economic sanctions, to deal with transactions with the likes of the Palestinian group Hamas and North Korea. IEEPA is not a general trade statute. It does not mention tariffs. Within the purposes for which it had been applied, it made sense to limit trade with bad actors, those who would harm the United States. Who else but the president should Congress have given authority to, to declare emergencies? It would destroy the usefulness of the statute if Congress has to begin deliberating about what an emergency is when a real one comes along.

The built-in guardrail was that Congress could override the declaration of emergency. But in an unrelated Supreme Court case, a vote in both houses of Congress was found to need the president’s signature to have any effect. This was accompanied by a natural reticence of the courts to seek to overturn a presidential emergency. Who told the judges they should intervene in matters of the highest national importance in foreign affairs, it would be argued. Result: Carte blanche was given to the presidency; there would effectively be no guardrails.

Then there was the matter of precedent. It was said that President Richard Nixon had imposed an import surcharge in 1971 during a real balance of payments emergency using predecessor authority, the Trading with the Enemy Act (TWEA). In 2025, numerous trade experts and three courts set off looking at the “precedent” of the supposed use of the 1917 statute. A clue should have been that that Nixon’s proclamation did not cite that authority. But the president’s proclamation was drafted in tight secrecy. Outside of two Treasury Department lawyers, only the Assistant Attorney General William Rehnquist (later Supreme Court chief justice) saw it. In fact, the historical record is now crystal clear that President Nixon had been adamant in discussions with his aides at closed meetings at Camp David, again secret at the time, that he was not going to invoke the wartime emergency authority because it was an insult to call our allies “enemies.”

Why does this matter? Because when President Trump did employ emergency authority, the 1971 tariff use precedent was baked into legal lore, that in an emergency, Nixon had imposed an import surcharge for a very short time (four months). That should not have mattered for events 50 years later. And the mistaken belief persists to this day that Trump could do the same with tariffs in an emergency as had been done under the Trading with the Enemy Act, the nearly identical predecessor to IEEPA that Trump invoked. But two generations ago, desiring to stop a repeat of what Nixon did with tariffs (although he in fact had used other authority), Congress passed a law in 1974 that in a balance of payments crisis, the president could impose up to an additional 15 percent tariff for up to 150 days. After that, the Congress would take over total control of setting tariffs. Congress had declared what to do in an emergency, and the authority was tightly limited.

In 1977, Congress restored the general emergency authority, IEEPA, trimmed down, for peacetime use. But no one thought it provided general tariff authority. The statute does not even mention tariffs. It is telling that the bill to create IEEPA was not referred to the committees with jurisdiction over tariffs. Congressional committees are very jealous of their jurisdictions. It cannot have been an oversight on their part to have ignored the passage of a bill that could equally be used to impose additional tariffs on everything from everywhere. As international trade lawyer Leonard Shambon explains, “neither committee with tariff jurisdiction believed that the bill concerned any significant delegation of tariff authority to the President.” It was an economic sanctions bill.

On the Trump tariffs, three courts found correctly that IEEPA included no extensive tariff authority, if it had any at all. But the strange history of Nixon’s surcharge with the incorrect supposition that he had invoked TWEA persists: Government lawyers argued 50 years ago and again in 2025 that these two authorities, TWEA and IEEPA, contained emergency broad tariff authority. It was convincing to four Federal Circuit appellate justices (none appointed by President Trump) for them to find this last year that broad tariff authority did exist in the more recent statute IEEPA.

This was how the Trump “reciprocal” tariff case finally got to the Supreme Court, which is about to rule on one of the most important constitutional questions of our age—on the separation of powers between the Congress and the president.

The claimed emergency tariff authority, not even mentioned in the statute, and not anywhere recorded in Congress’s consideration of the legislative authority cited by the president’s lawyers, never existed at all.

It is fitting that during the 250th year celebration of the country’s birth that it is recognized that the constitution granted the power to set tariffs to the Congress not the president.