Why the Supreme Court should strike down Trump’s tariff authority

I have two points to make on this issue: first is a broader point, and, second, a legal analysis. 

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1. MAGA have given up on the American system of government

President Trump justified the tariffs, as usual, by invoking a national emergency.

And, why is that?

I think it’s because MAGA is that contingent of the right-wing that regard the Constitution as a museum relic.

It’s almost always a response of “but the Democrats ...”. If the Democrats abused power, then abuse of power is the new norm. In a very real sense, MAGA doesn’t really believe in the democratic republic anymore. They aren’t concerned with things like separation of powers, federalism, constitutional conventions etc.

MAGA are liberated from the quondam ideals of conservatism. They don’t at all believe in things that I regard as a virtue in government: self-restraint, the inherent desire for limited-government, checks-and-balances, deep skepticism of concentrated power, the norms of due process, not being swayed by the “passions of the moment”.

For example, judicial review, or the complex process of passing a bill, are classic examples of especially conservative governance that we get from the Founders. They are mechanisms of restraint to force compromise, reconsideration and long-term thinking. The separation of powers and federalism are not merely tools of efficiency; they are designed to limit power by dividing it and making it compete with itself.

MAGA see an opportunity, and call it a “crisis” or “emergency”, because they consider these old-fashioned notions outdated & frustrating obstacles towards their goals. MAGA doesn’t understand that, as a result of the system itself, they’ll lose occasionally. Many don’t even understand that the system was designed that way. For them, every defeat becomes a missed opportunity to solve a problem. They are Nietzscheans, just like the post-modernists. Radicals even. 

To me, it seems so obvious that national security is the inherent competence of Congress. To the extent that we are threatened, it is upon their authority to control trade with hostile nations. For example, by imposing on transactions the cost of its related externalities (such as regulating oil with Iran, or the fishing industry to mitigate the blight of overfishing etc). However, such power should be as limited as possible - not as expansive as possible (see below). Especially if the President turns out to be a moron.

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2. Is it against constitutional principles?

It doesn’t look it.

Andrew C. McCarthy has written (in “Trump Is Down, but Not Out, in the Tariffs Court Case”, NR) that, while it seems elementary that taxes are the business of Congress, the courts (including liberal judges) have accepted that the Presidency has in fact been empowered by the IEEPA. 

The IEEPA granted the President power to “regulate international commerce” after declaring a “national emergency” in response to “any unusual and extraordinary threat” to the United States. As he says, “even though Trump lost, he persuaded seven of the eleven judges that the IEEPA gives presidents tariff authority, to some extent”.

I have excerpted him at length below as he raises some very interesting points about how our constitution has (unfortunately) evolved towards greater executive power. Against this tide, the US Supreme Court has ruled (in favour of strengthening the legislature’s inherent power) by ruling that, in respect of “major questions” of public policy, legislative power cannot be assumed to have been delegated via vague and general language. It needs to be expressly rendered. This was the basis on which the judiciary - correctly, in my view - struck down Biden’s efforts to govern without Congress in the student loan forgiveness case of Biden v Nebraska (2023).

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Trump Is Down, but Not Out, in the Tariffs Court Case
By Andrew C. McCarthy
September 6, 2025 6:30 AM

This is not a constitutional law case; it is a statutory interpretation case. It is not about delegation; it is about what is meant by Congress’s grant in the IEEPA of presidential authority to “regulate” imports — i.e., are tariffs encompassed within regulatory power? (in other words, we just have to accept that Congress has empowered the President - the question is to what extent). We must stop focusing on delegation. That ship has sailed. Let’s just stipulate that we conservatives would like to pare back Congress’s penchants to delegate its powers and to prescribe vaguely defined “emergencies” as a pretext enabling presidents and executive agencies to legislate (a joke) ...

Fretting over delegation will cause you to miss one of the best arguments against the tariffs ... Remember, in the IEEPA, neither the word tariff nor any of its close analogues (e.g. duty, surcharge, or tax) appears. Sure, maybe Congress should never have delegated tariff authority in any statute; but the statutes in which it has done so powerfully illustrate that, when Congress truly intends to delegate tariff authority, it requires the executive to jump through many procedural hoops, and it restricts the amount of exaction the executive may prescribe, as well as its duration ... That’s a strong argument against the tariffs, especially when conjoined with two other points (lack of conditions and oversight by the legislators). First, in the IEEPA’s near half-century on the books, no president prior to Trump had invoked it as a rationale for imposing tariffs. Second, in enumerating Congress’s powers, Article I of the Constitution separately confers the powers (a) “to lay and collect Taxes, Duties, Imposts and Excises” and (b) “to regulate Commerce with foreign Nations”; if the Framers had intended the power to tax (including to impose tariffs) to be subsumed by the power to regulate foreign commerce, there would have been no need to have discrete provisions (an interesting point that goes to regulating being separate conceptually from taxing).

The tariffs were challenged in Yoshida International v. United States (in the Nixon era) ... Just as in the Trump tariffs case, the lower court ruled against the president, concluding that the TWEA’s authority to regulate did not include the power to impose tariffs. On appeal, however, the CCPA reversed, reasoning that the word “regulate” encompassed tariffs that were “appropriately and reasonably related . . . to the particular nature of the emergency declared.” ... These judges thus rejected Trump’s tariffs only because they were not as deliberative and reasonable as Nixon’s. By contrast, the four dissenting justices would have gone all the way with Trump — deferring to a president’s foreign policy and national security judgments — a position Yoshida plainly supports. (This shows that the courts (incl. liberal judges) have been minded to agree with Trump on the history/scope of the power).

Why the Nixon Precedent Is Inapposite ... one of the salient purposes of the IEEPA — in conjunction with another post-Watergate statute, the 1976 National Emergencies Act — was to curtail the president’s ability to usurp legislative authority by the facile declaration of emergencies. Over time, ironically, the statutes seem to have had the opposite effect ...

For originalists, that should be the end of the case. Nevertheless, because the non-political branch is self-aware that national security or foreign policy are political matters that lie outside the judicial ken, there is a tendency to defer to the president in cases touching on such matters. Perhaps that makes sense when a private litigant, particularly a non-American, is challenging a president’s actions on the world stage, or when national security risks are palpable. But deference to the president is inappropriate in a case that turns on the separation of powers between the political branches. In that situation, any deference to the president could only come at Congress’s expense. (Good argument here, that the scope of the power is abridged by the separation of powers considerations - but I don’t think the courts are that concerned about Congress’ powers). The Framers gave Congress, not the president, the power to regulate foreign commerce and impose tariffs on imports. If anything, then, there should be a presumption against presidential action absent an unambiguous congressional grant of authority ...

Second, it is worth revisiting Biden v. Nebraska (2023), in which the Court rejected the last administration’s attempt to massively cancel student loans. I invite your attention, in particular, to Justice Elena Kagan’s spirited dissent. She berated her conservative colleagues over what she portrayed as their textualist pretensions. The statute at issue (the so-called HEROES Act) empowered the executive branch (the secretary of Education) to “waive or modify any statutory or regulatory provision” and to replace old loan agreements with new “terms and conditions.” For Kagan, the plain reading of the text — i.e., giving the words their most commonly understood meaning — easily embraced cancelation (indeed, she faulted the majority for overhyping the word modify in isolation, decoupling it from waive, which is undeniably close to cancel). Further, she scolded her conservative colleagues for resorting to the “major questions” doctrine — the concept that Congress must be especially clear if it intends to empower the executive power to take actions that have vast economic or political significance. In Kagan’s telling, this is just an artifice by which self-proclaimed textualists evade text when they don’t like the result it portends. (This contention prompted a thoughtful response from Justice Amy Coney Barrett, who concurred in the ruling against Biden’s loan cancellations. Barrett countered that the major questions doctrine is a valuable tool for illuminating the context of the statute, not for nullifying its text.) Intriguingly, the Federal Circuit’s majority opinion against Trump’s tariffs relies heavily on the major questions doctrine. (I think Justice Elena Kagan is trapped and exemplifies the flaw of contextualism. She excoriated her judicial colleagues against adopting the “major questions” doctrine when it came to Biden’s desire to override an inherently Congressional power. How does she push back against Trump? Her school of thought is purposive interpretation. I.e. we should interpret the text in light of the context for which it was written (national emergency) and to achieve its stated purpose (regulate international commerce)).

Of course, the tariffs case is different from the loan forgiveness case because the contested statutory word in the former, regulate, has constitutional pedigree (as we’ve seen, Article I does not subsume the power to impose tariffs in the power to regulate foreign commerce). Even with that said, her Biden v. Nebraska dissent makes it hard for me to foresee Justice Kagan voting against the Trump tariffs, and she is one of the most influential justices on the Court. Consider that in conjunction with the number of Democratic-appointed judges who have signaled sympathy for the premise that the IEEPA empowers a president to impose tariffs. Doing so convinces me that many progressives like the idea of a future Democratic president unilaterally imposing tariffs in an effort to manage the economy — even if they have to let Trump wield that power for the next three years. (I think so too - that ship has sailed already).