On February 20, 2026, the U.S. Supreme Court delivered a major separation-of-powers decision in Learning Resources, Inc. v. Trump, voting 6–3 to invalidate President Donald Trump’s sweeping “reciprocal” and “trafficking” tariffs that had been imposed through executive orders under the International Emergency Economic Powers Act (IEEPA). The Court’s core holding was narrow but consequential: IEEPA authorizes the president to regulate certain economic activity during a declared national emergency, but it does not clearly delegate Congress’s constitutional power to impose tariffs and duties. In Chief Justice John Roberts’ framing, reading two words in IEEPA (“regulate” and “importation”) as a blank check to levy tariffs “at any rate, for any amount of time” asks language to carry weight it cannot bear, and the statute contains no explicit reference to tariffs or duties.
This is not a “tariffs are over” moment. It is a “the shortcut is closed” moment. The Court did not say trade pressure is illegitimate or that tariffs are inherently unlawful; it said that if the executive branch wants to impose measures of vast economic consequence, it must do so with clear congressional authorization. The majority also leaned on the “major questions” doctrine: when an action has enormous economic and political significance, Congress must speak clearly if it intends to delegate such power.
The immediate market and policy implication is that tariffs can persist—through different legal pathways. The United States has a well-stocked toolbox of trade statutes that presidents have used for decades. Section 232 of the Trade Expansion Act of 1962 allows restrictions, including tariffs or quotas, after a Commerce Department investigation finds that imports threaten national security. This mechanism has been used repeatedly in modern U.S. trade policy and is structurally easier to defend in court because it rests on a long-established delegation framework tied to national security. Section 301 of the Trade Act of 1974 empowers the U.S. Trade Representative to investigate unfair foreign trade practices and recommend responsive measures, including tariffs—often without waiting for a WTO dispute to conclude.
There are also faster, more temporary options. Section 122 of the Trade Act of 1974 can authorize short-term across-the-board import surcharges in response to balance-of-payments or related external financial conditions, but it is time-limited (commonly described as up to 150 days) and capped in rate. In practical terms, the Supreme Court ruling forces any administration that wants tariff leverage to either (1) run the procedural track of investigations, findings, and reports under the trade statutes, or (2) use short-duration emergency-style tools that do not pretend to be a permanent replacement for congressional tariff authority.
Another key consequence is legal and diplomatic uncertainty around deals negotiated in the shadow of the now-invalid IEEPA tariffs. SCOTUSblog’s analysis notes the Court did not decide whether refunds must be issued to importers who paid the tariffs, while also warning that the decision could create uncertainty for trade arrangements facilitated by the tariff regime. If importers pursue litigation for refunds at scale, the timeline could be long, politically fraught, and commercially disruptive—especially if costs were passed through supply chains to downstream buyers.
For Taiwan, the issue is not simply “what is the tariff rate next week.” The deeper risk is negotiation volatility and supply-chain planning under shifting U.S. legal authorities. When tariff authority migrates from IEEPA to statutes like 232 or 301, the burden of proof, the target scope, and the bargaining logic can change. A 232-centered regime tends to focus on strategic sectors and national security framing—exactly where Taiwan’s semiconductor and advanced manufacturing ecosystem is most exposed. A 301-centered regime can become highly country-specific and expansive across product categories if USTR determines patterns of discrimination or unreasonable practices.
That means Taiwan’s best defense is not reactive commentary about a single Supreme Court ruling; it is building a durable U.S. trade posture that survives changes in the White House and pivots in legal strategy. Practically, this pushes Taiwan toward three priorities: (1) reduce single-statute dependency by structuring understandings that are defensible under multiple U.S. legal authorities; (2) deepen congressional-facing engagement, because the Court’s logic re-centers Congress’s constitutional role in tariffs; and (3) operationalize supply-chain contingency plans—contract clauses, pricing pass-through terms, alternative routing, inventory buffers, and compliance workflows—so that a shift from broad tariffs to targeted sector actions does not become a sudden corporate crisis.
The Supreme Court just told the world that the U.S. system still draws lines around presidential economic power. That may improve long-run predictability, but it also guarantees near-term turbulence: administrations will keep seeking tariff leverage, just with different statutes, different procedures, and different targets. Taiwan’s real test starts after the IEEPA shortcut ends—when the U.S. tariff playbook becomes more procedural, more sector-focused, and more negotiation-driven than before.
Author : Cathy Lin
