Inside Trump's Section 301 Offensive: 16 Trade Probes That Could Reshape Global Commerce

On March 11, 2026, the Office of the United States Trade Representative announced the most expansive use of Section 301 of the Trade Act of 1974 in the statute's half-century history. Sixteen economies — representing the vast majority of U.S. imports — are now the subjects of formal trade investigations that could result in sweeping new tariffs on everything from automobiles and semiconductors to agricultural goods and consumer electronics [1][2].

The investigations are not merely a policy choice. They are a legal necessity. Three weeks earlier, the Supreme Court struck down the cornerstone of the Trump administration's tariff architecture, ruling 6-3 that the International Emergency Economic Powers Act does not grant the president authority to impose tariffs [3]. Now the administration is scrambling to reconstruct its trade barriers on firmer legal ground — and the clock is ticking.

The Supreme Court Blow That Changed Everything

The February 20 ruling in Learning Resources, Inc. v. Trump was a landmark. Chief Justice John Roberts, writing for a majority that included Justices Sotomayor, Kagan, Gorsuch, Barrett, and Jackson, held that IEEPA's "lengthy list of powers is absent any mention of tariffs or duties" and that "had Congress intended to convey the distinct and extraordinary power to impose tariffs, it would have done so expressly" [3][4].

The decision invalidated the entire IEEPA-based tariff regime — the reciprocal tariffs imposed on nearly all countries beginning in April 2025, the fentanyl-related tariffs on China, Mexico, and Canada, and the country-specific rates that at their peak pushed the effective U.S. tariff rate from 2.5% to an estimated 27%, the highest level in over a century [5][6]. The Penn-Wharton Budget Model estimated that IEEPA-based tariff collections totaled approximately $175 billion to $179 billion, exceeding the combined fiscal 2025 spending of the Departments of Transportation and Justice [4].

Within hours of the ruling, the White House moved to stanch the bleeding. President Trump signed an executive order invoking Section 122 of the Trade Act of 1974, declaring that the United States faces "fundamental international payments problems" and imposing a flat 10% surcharge on all imports effective February 24 [7][8]. But Section 122 comes with hard constraints: a maximum rate of 15% and a maximum duration of 150 days without congressional action. That clock runs out on July 24, 2026 [8].

The Two-Stage Strategy

The administration's approach has been described by trade lawyers as a two-stage strategy [9]. Section 122 provides rapid, blunt-force coverage — a 10% tariff floor on all imports to prevent a sudden collapse of the tariff regime. Meanwhile, Section 301 investigations run in parallel, building the legal and evidentiary record needed to impose targeted, potentially much higher tariffs that can remain in place indefinitely.

USTR Jamieson Greer announced that the goal is to conclude the Section 301 investigations before the Section 122 tariffs expire on July 24 [1]. The standard timeline for a Section 301 investigation is 12 months, but the administration plans to operate on an "accelerated timeframe" consistent with the statute's procedural requirements [10].

The docket opened on March 11, with a deadline for written public comments set for April 15 and public hearings expected around May 5 [2]. After that, the USTR must consult with the trading partners under investigation before proposing responsive action.

"Responsive action can take a number of forms," Greer said. "It can be tariffs, it can be fees on services, it can be other things" [1].

The 16 Targets

The investigations cover a sweeping cross-section of U.S. trade relationships [1][2][11]:

Top-tier targets (largest U.S. goods trade deficits):

• European Union — $218.8 billion goods deficit in 2025, the largest of any partner
• China — $202.1 billion goods deficit in 2025
• Mexico — $196.9 billion goods deficit in 2025

Major Asian economies:

• Japan, South Korea, Taiwan, India, Vietnam

Southeast Asian manufacturing hubs:

• Indonesia, Malaysia, Cambodia, Thailand, Bangladesh, Singapore

European outliers:

• Switzerland, Norway

The total 2025 U.S. goods and services trade deficit stood at $901.5 billion, down only marginally from $903.5 billion in 2024, despite a year of aggressive tariff action [12]. That figure is central to the administration's argument that existing trade relationships are fundamentally imbalanced.

Source: Bureau of Economic Analysis

Data as of Feb 19, 2026CSV

What the Investigations Are Actually Probing

The Section 301 probes focus on what the USTR describes as "structural excess capacity and production in manufacturing sectors" — the allegation that foreign governments subsidize domestic production beyond what markets demand, flooding global markets with cheap goods and undercutting American manufacturers [1][2].

This framing borrows heavily from the long-running U.S. critique of Chinese industrial policy, but the administration is applying it far more broadly. The investigations will also examine:

• Digital services taxes imposed by trading partners, which U.S. tech companies have long opposed
• Alleged currency manipulation that makes foreign exports artificially cheap
• Non-tariff barriers such as regulatory standards, procurement preferences, and licensing requirements
• Larger, persistent trade surpluses or underutilized production capacity [2][11]

The breadth of this approach is significant. Previous Section 301 investigations — most notably the 2018 probe into Chinese intellectual property practices that launched the first Trump trade war — targeted individual countries for specific practices. The 2026 probes apply a single investigative framework across 16 economies simultaneously, covering nearly every major U.S. trading partner outside of Canada, the United Kingdom, and Australia.

Market Reaction and Economic Uncertainty

Financial markets have reflected the uncertainty. The S&P 500 has traded in a volatile range since the Supreme Court ruling, falling from approximately 6,910 on February 20 to 6,776 by March 11 [13]. The index has struggled to find direction as investors weigh the competing forces of tariff reduction (the IEEPA tariffs being struck down) and tariff reimposition (Section 122 and the prospect of Section 301 tariffs).

Source: FRED / S&P Dow Jones Indices

Data as of Mar 11, 2026CSV

The U.S. trade deficit data tells its own story. Monthly goods and services deficits swung wildly through 2025, spiking to $136 billion in March as importers front-loaded purchases ahead of expected tariff increases, then collapsing to under $29 billion in October before rebounding to $70 billion in December [12].

Source: FRED / Bureau of Economic Analysis

Data as of Feb 19, 2026CSV

Treasury Secretary Scott Bessent has predicted that by August, U.S. tariffs would return to the levels that existed before the Supreme Court's ruling [14]. That would represent a significant escalation from the current flat 10% Section 122 rate, potentially restoring country-specific rates that reached as high as 50% on some trading partners.

The Economic Toll So Far

The tariff regime's impact on American households has been substantial. The Tax Foundation estimates that the Trump tariffs amounted to an average tax increase per U.S. household of $1,000 in 2025 and $1,300 in 2026 [5]. A Federal Reserve Bank of New York study found that between 6% and 14% of tariff costs were absorbed by foreign exporters, while studies by the National Bureau of Economic Research and the Kiel Institute estimated that U.S. consumers and businesses bore 94% to 96% of the costs [6].

Corporate bankruptcies in the United States increased to the highest level since 2010, driven in part by supply chain disruptions and input cost increases [6]. Consumer confidence declined sharply, with more than half of Americans blaming the administration for rising costs of living [6].

The trade deficit itself has barely budged. Despite the most aggressive tariff regime in a century, the 2025 deficit fell only $2.1 billion — a 0.2% decrease — from 2024 levels [12]. Critics argue this demonstrates that tariffs are an ineffective tool for reducing trade imbalances, while the administration contends that the deficits reflect deeply embedded structural distortions that the new Section 301 investigations are designed to address.

Trading Partners in Limbo

The investigations come at a particularly fraught moment for U.S. trade diplomacy. Several deals struck during the tariff escalation of 2025 are now in jeopardy.

The European Parliament has twice postponed a vote on the trade deal that would set a 15% U.S. tariff rate on most EU goods while eliminating European tariffs on many American imports. Bernd Lange, chair of the European Parliament's international trade committee, has said the U.S. breached the terms of its deal and that the bloc is "prepared to retaliate if necessary" [14].

India paused plans to finalize an interim trade deal, with Trade Minister Piyush Goyal stating his country would resume talks "when there is more clarity" [14]. Japan and South Korea, both close security allies, now find themselves subject to the same investigative framework as adversarial economies like China.

The U.S.-China trade relationship remains the most fraught. After a tit-for-tat escalation that pushed bilateral tariffs to 125% in April 2025, the two countries agreed to a 90-day reduction to 10% in May 2025 [6]. But with new Section 301 investigations underway, the fragile détente faces renewed pressure.

Legal and Constitutional Questions

The pivot from IEEPA to Section 301 does not eliminate legal risk for the administration. Trade law experts have noted that while Section 301 provides clearer statutory authority for tariffs, the process must be followed faithfully [9][10]. The accelerated timeline raises questions about whether the USTR can conduct genuinely meaningful investigations, complete public comment periods, consult with trading partners, and issue formal findings in roughly four months.

The Section 122 tariffs themselves face potential legal challenges. While Section 122 explicitly authorizes temporary import surcharges, some scholars question whether the current U.S. balance-of-payments situation truly constitutes the "fundamental international payments problems" the statute requires [15]. A challenge could reach the courts before the 150-day window expires.

There is also the question of what happens if the Section 301 investigations are not complete by July 24. The administration could theoretically allow the Section 122 tariffs to lapse, declare a new emergency, and restart the 150-day clock — creating what analysts have described as a "de facto perpetual tariff instrument" [8]. Whether courts would tolerate such a maneuver remains untested.

What Comes Next

The next four months will determine the trajectory of U.S. trade policy for the foreseeable future. The key milestones:

• April 15, 2026: Deadline for public comments on the Section 301 investigations
• ~May 5, 2026: Expected public hearings
• July 24, 2026: Expiration of Section 122 temporary tariffs
• August 2026: Treasury Secretary Bessent's predicted date for tariff rates to return to pre-ruling levels

If the administration successfully completes its Section 301 investigations and imposes new tariffs before July 24, it will have achieved a remarkable legal and bureaucratic pivot — replacing a tariff regime built on questionable executive authority with one grounded in a well-established statutory framework. If it fails to meet that deadline, the United States could face a gap in tariff coverage that would send shockwaves through supply chains and markets worldwide.

For the 16 economies under investigation — and the thousands of businesses that depend on trade with them — the uncertainty alone is already exacting a cost. As one trade attorney quoted by CBS News put it, "the tariff rate almost doesn't matter anymore. It's the unpredictability that's killing us" [16].