The battle over President Donald Trump’s tariffs is entering a new phase after Democrats captured control of Congress in the November 3, 2026, midterm elections. Oregon Senator Ron Wyden, the incoming chairman of the powerful Senate Finance Committee, is preparing to challenge the White House’s sweeping authority over American trade policy.
Canada could become one of the central battlegrounds. Wyden has already criticized Trump’s tariffs on Canadian goods and introduced legislation designed to return greater control over trade decisions to Congress. His emerging agenda could bring tougher scrutiny of tariffs, new investigations and renewed pressure to reconsider measures affecting businesses on both sides of the border.
However, with Trump remaining president, congressional opposition does not guarantee immediate tariff relief.
A Midterm Victory Changes Who Controls the Trade Debate
The November 3 elections did more than reshape party numbers in Washington. Democrats won both chambers of Congress, clearing a path for Wyden to move from the top Democratic position on Senate Finance into the chairmanship when the new Congress organizes in January 2027. Wyden has led the committee before, giving him extensive experience with the complicated relationship between taxes, trade agreements and executive authority. In his November 4 statement, he placed affordability and accountability at the centre of his plans and identified congressional control over trade as a priority. The result represents a significant change from the Republican-led Congress, where Democrats had considerably less control over committee investigations and legislative priorities.
The chairmanship matters because Senate Finance is one of the principal congressional committees responsible for trade and tariff legislation. Its leadership can organize hearings, request testimony, demand explanations from federal agencies and pursue investigations using committee procedures. Bloomberg Government reported that Wyden’s position will also strengthen his ability to scrutinize Treasury nominees and use subpoena powers. None of those tools automatically cancels an existing tariff. For a Canadian manufacturer pricing a shipment or an American buyer negotiating a supply contract, however, the shift introduces a new political reality. Decisions previously driven largely by the White House could face considerably more public scrutiny, with congressional investigators examining their economic effects and legal foundations.
Wyden Already Has Legislation Designed to Limit Presidential Tariff Powers
Wyden did not wait for Democrats to regain congressional control before outlining his approach. On July 22, 2026, he introduced Senate Bill 5081, known as the Congressional Trade Powers Reform Act of 2026. The legislation proposes significant changes to the authority Congress has delegated to presidents over international trade. Its provisions include repealing Section 338 of the Tariff Act of 1930 and Section 122 of the Trade Act of 1974, while modifying other presidential trade powers dealing with national security, import competition and unfair trade practices. The proposal also seeks to require congressional approval for trade agreements that create binding obligations for the United States, providing lawmakers with greater authority over decisions that can affect entire industries.
The distinction between a proposed reform and an enacted law remains important. Government records show that Wyden’s legislation was introduced and referred to the Senate Finance Committee, without advancing to a final congressional vote. Because legislation generally expires at the end of a two-year Congress, the proposal would need to be reintroduced in the next Congress if it remains unfinished. Nevertheless, the July measure provides a concrete indication of what Wyden wants to accomplish. For businesses that import raw materials, machinery or finished products, the underlying issue extends beyond any particular president. Companies need predictable costs to make investment decisions, and sudden changes in tariff policy can disrupt contracts negotiated months before products reach the border.
Canada’s 50% Tariffs Have Become a Major Flashpoint
Canada occupies a particularly important place in Wyden’s trade agenda because the Trump administration has used an unusually old provision of American law to impose substantial duties on Canadian products. On July 20, 2026, the White House announced additional tariffs of 50% on selected Canadian goods under Section 338 of the Tariff Act of 1930. The measures took effect on August 22 after a brief postponement, affecting products across several industries, including furniture, plastics, machinery, electronics and wood products. The administration subsequently revised the product lists several times. Its latest changes, effective October 30, removed 22 tariff classifications while adding another 100, demonstrating how quickly the costs facing individual importers can change.
Washington maintains that the tariffs respond to Canadian policies affecting American automobiles, alcoholic beverages and dairy products. Ottawa disputes key aspects of that characterization, arguing that some Canadian restrictions were responses to earlier American tariffs and that its dairy quota administration complies with CUSMA obligations. Canada also introduced retaliatory duties on approximately C$27.6 billion worth of American goods in September. Importantly, the additional Section 338 tariffs can affect goods that otherwise qualify for preferential treatment under the continental trade agreement. For Canadian exporters, that creates a difficult situation. A manufacturer may satisfy CUSMA’s rules of origin yet still face significant American import duties, making cross-border business considerably less predictable than the agreement was designed to encourage.
A Nearly Century-Old Law Is Driving the Dispute
Section 338 originates from the Tariff Act of 1930, commonly associated with the Smoot-Hawley era of American trade protectionism. It authorizes a president to impose additional duties of up to 50% when another country is determined to discriminate against American commerce under the conditions specified in the law. The provision also permits restrictions on imports if the alleged discrimination continues or intensifies. Congressional Research Service analysis identified Trump’s 2026 actions against Canada as the first time an American president had expressly relied on this provision to impose tariffs. That unprecedented use is central to the political controversy, raising questions about whether legislation written for a different economic era should provide such extensive modern trade authority.
The legal discussion became more complicated after a major Supreme Court ruling on February 20, 2026. In Learning Resources, Inc. v. Trump, the court determined that the International Emergency Economic Powers Act did not authorize the president to impose tariffs. The decision invalidated tariffs issued under that particular statute, but it did not eliminate the other tariff powers Congress had previously delegated to the executive branch. Authorities under Sections 232, 301 and 338 remained separate legal mechanisms. That distinction explains why Wyden’s proposed reforms go beyond challenging individual presidential decisions in court. His objective is to change the statutory framework itself, potentially preventing future administrations from relying on broad delegations of power to make abrupt changes to international trade policy.
The Economic Consequences Extend Beyond Individual Tariff Rates
One of the most important distinctions in the dispute is that the 50% tariffs do not apply universally to every Canadian export. Many shipments continue to benefit from preferential trade arrangements, while higher duties target particular industries and products. Nevertheless, the economic implications extend well beyond the businesses directly affected. In an assessment published October 20, Canada’s Parliamentary Budget Officer estimated that recent trade measures had increased the trade-weighted average effective American tariff on Canadian imports from 5.3% to 7.7%. The same analysis projected that trade restrictions introduced since early 2025 could leave Canadian real GDP approximately 1.4% lower after five years compared with a hypothetical scenario in which the previous trading relationship had continued. Those figures represent estimated economic effects rather than losses already realized.
Employment is another concern. The Parliamentary Budget Officer estimated that, if the tariffs remain permanent, the combined trade measures could reduce Canadian employment by as many as 185,000 jobs at their peak relative to the pre-tariff baseline. American businesses also experience costs, particularly when imported components become more expensive. Research published by the Federal Reserve Bank of New York estimated that approximately 26% of the 2025 tariff increases studied passed through to consumer prices, including indirect effects on domestically produced goods. That estimate is not specific to Canada’s latest tariffs, but it illustrates the economic mechanisms involved. A higher price for imported materials can eventually affect factory production costs, retail prices and purchasing decisions, even when consumers never directly purchase the imported product.
Congressional Hearings Could Expose How Tariff Decisions Are Made
One of Wyden’s most consequential opportunities may come through investigations rather than immediate legislation. The Senate Finance Committee has jurisdiction over tariffs, customs administration, reciprocal trade agreements and important elements of federal trade policy. Under its existing procedural rules, the chairman can organize hearings and pursue subpoenas with the ranking minority member’s agreement or a committee majority vote. That creates opportunities to question administration officials about the evidence supporting individual tariff decisions, the process used to select affected products and the treatment of businesses requesting exemptions. An importer that suddenly faces a substantially higher duty could become part of a broader discussion about whether tariff measures are being applied consistently and transparently.
The potential investigation could extend to how tariffs affect American workers, small businesses and consumers. Reuters reported before the election that Democratic control of congressional trade committees could lead to greater scrutiny of tariff exemptions, corporate arrangements and the administration’s trade commitments. Public testimony from manufacturers, agricultural producers, retailers or trade specialists could provide evidence that would otherwise receive limited attention outside Washington. Wyden has also indicated that his broader committee agenda will examine tax compliance and the practices of major companies, including health insurers, banks and pharmaceutical businesses. These priorities may compete for committee time, making the eventual hearing schedule important. However, even without legislative changes, sustained oversight could increase political pressure on the administration to justify its trade policies.
Trump’s Veto Power Remains a Major Obstacle to Tariff Reversal
Despite Democrats winning control of Congress, eliminating Trump’s tariffs would remain politically difficult. Under the U.S. Constitution, legislation passed by the House and Senate must ordinarily receive the president’s signature to become law. If Trump vetoes a tariff-repeal measure, Congress would need a two-thirds majority in both chambers to override his decision. The Democratic election victories do not automatically provide those supermajorities. Nevertheless, lawmakers already have legislation that could form the basis of another attempt. In September, Senate Democratic Leader Chuck Schumer introduced the End Trump’s Tariff Tax Act, with Wyden among its supporters. The proposal seeks to terminate certain presidential tariffs, repeal the statutory authorities behind them and provide refunds for duties collected under the affected measures.
The situation is complicated by differing views within the Republican Party. Some Republicans have defended Trump’s use of tariffs as a negotiating instrument, arguing that trade barriers can pressure foreign governments to open markets to American products. Republican Senator Chuck Grassley, however, has also supported restoring a stronger congressional role in tariff decisions. Following the Supreme Court’s February ruling, Grassley advocated legislation giving Congress greater influence while continuing to praise Trump’s trade negotiations. Such positions suggest that bipartisan cooperation on procedural reforms may be more achievable than agreement on abolishing specific tariffs. For Canada, this distinction is crucial. More congressional scrutiny could strengthen the case for relief, but meaningful reductions would still require executive action, enacted legislation or another legally effective decision.
Ottawa Faces a New Congressional Landscape While Trade Negotiations Continue
The transition in Washington comes as Canada and the United States are attempting to revive negotiations that deteriorated during the summer. On November 3, Prime Minister Mark Carney reported that more intensive discussions had begun and that Washington had withdrawn some earlier demands. Those included proposed restrictions on Canada’s ability to negotiate trade agreements with other countries. Carney characterized the American position as involving fewer demands and more favourable offers, while emphasizing that significant disagreements remained unresolved. Trump also expressed optimism about reaching an agreement. However, no completed deal or comprehensive new tariff-relief package had been announced. That leaves Canadian exporters facing the same immediate challenge: business decisions must be made under existing trade rules, even as political leaders signal that negotiations could produce changes.
Another important milestone is approaching through the Canada-United States-Mexico Agreement. The first mandatory joint review occurred on July 1, 2026, but Washington declined to extend the agreement in its existing form. CUSMA remains in force, with annual reviews required until the parties agree to extend it or its existing term expires. The Office of the U.S. Trade Representative has already opened consultations ahead of the 2027 review, with written submissions due January 12, 2027. Wyden’s incoming chairmanship could give congressional concerns greater visibility during this process, although negotiations remain primarily an executive responsibility. For Ottawa, the immediate priority is obtaining reliable tariff relief while protecting Canadian industries and negotiating authority. The larger question is whether Washington’s new balance of political power can produce a more stable trading relationship rather than another prolonged period of uncertainty.
