In mid-September 2025, the Trump Administration announced two new Section 232 inquiries aiming to substantially broaden the range of imports subject to high tariffs. One inquiry focuses on steel and aluminum products, potentially extending the 50% duty (imposed earlier in 2025) to additional derivative goods. A companion investigation targets automotive components: whereas prior tariffs applied mainly to passenger vehicles and a subset of parts, the new probe aims to capture a much wider array of auto parts under a 25% tariff. According to official summaries, the auto parts review was spurred by U.S. industry requests and could pull many additional components into the existing tariff regime. Past practice under Section 232 suggests each new investigation typically leads to tariff action, so European producers can expect forthcoming duty increases on these products. Notably, the Administration has also launched Section 232 investigations into advanced manufacturing machinery (industrial robots, CNC machine tools, etc.) and critical medical supplies. The Department of Commerce issued Federal Register notices on September 2, 2025, opening inquiries into “robotics and industrial machinery” and into personal protective equipment and medical consumables and devices. These notices raise the question whether these imports – ranging from surgical masks, gloves, and syringes to hospital beds, imaging machines, pacemakers, and insulin pumps – threaten U.S. national security.

Alongside new investigations, U.S. regulators have issued rules to facilitate adding products to existing tariff lists. In September 2025, the Bureau of Industry and Security opened a two-week “inclusions window” for steel and aluminum. At the same time, an interim final rule on automotive parts – mandated by Presidential Proclamation 10908 – established an analogous inclusion process for auto parts. The auto parts rule allows U.S. carmakers or trade associations to request that specific parts be added under the 25% tariff if import trends “threaten to impair national security.” In short, both rules create a formal procedure for the industry to nominate new tariff targets under Section 232, signaling that the government expects to extend tariffs to many more steel products and vehicle components.

These aggressive measures are designed to boost the domestic output of goods deemed critical to security. The administration has made no secret of its protectionist policy: the U.S. government is now “rapidly increasing” the use of Section 232 with a dozen active investigations by late September. Although tying items like rubber, lumber, or medical devices to national security is highly questionable, political opposition in the U.S. has so far been minimal. Critics warn that by continually expanding the scope of 232 tariffs, the U.S. is effectively restricting European exports on a broad front, despite any trade “agreements.” Every new review to date has been followed by new duties and European exporters face an increasingly complicated tariff environment where components of a product may carry different duty rates. The will likely worsen market access for EU goods in sectors ranging from automotive to machinery to medical equipment, according to government analysts.

In conjunction with these investigations, the U.S. formally began implementing the August 2025 EU–U.S. framework on reciprocal, fair trade. On September 5, 2025, the President issued Executive Order No. 14346, directing the Department of Commerce and USTR to implement agreed tariff modifications. On September 24–25, 2025, an official Federal Register notice amended the U.S. tariff schedule to carry out the deal’s tariff elements. Under these changes, most duties on certain EU exports were reduced to normal WTO (Most-favored Nation) levels or otherwise lowered. Notably, U.S. tariffs on passenger vehicles and light trucks made in the EU were cut from 25% to 15%. For EU-made automobile parts, the tariff schedule was amended so that the combined tariff rate (U.S. base rate plus any 232 duty) equals 15% on or after August 1. Meanwhile, U.S. tariffs on EU-origin aircraft and aircraft parts –elevated under prior Section 232 proclamations – were rescinded back to pre-232 levels. Similar treatment was given to “unavailable natural resources” (e.g., certain forestry products like cork) and generic pharmaceuticals: EU products in those categories will now pay only the regular MFN tariff, whereas non-EU suppliers, such as India for generics, continue to face higher duties.

Under the framework notice, these tariff cuts took effect with mixed retroactivity: changes for aircraft, pharmaceuticals, and related items apply as of September 1, 2025; changes for cars and auto parts apply from August 1, 2025. The U.S. announcement noted that refund or adjustment of duties paid since those dates will need to be addressed. These actions mark the fulfillment of key elements of the U.S.–EU agreement. In theory, this should stabilize bilateral trade relations. Analysts predict the competitive impact will depend on overall cost factors – for example, European drugmakers may gain an edge since they now face lower U.S. duties than large generic suppliers from India. The short- and long-term effects on the U.S. auto market are less clear, given that U.S. producers requested the tariff cuts as part of the deal.

The flurry of executive actions has heightened scrutiny of the president’s legal authority to set tariffs unilaterally. In August 2025, a federal appeals court struck down many of the Trump administration’s tariffs imposed under the International Emergency Economic Powers Act, ruling them unlawful. That judgment was stayed pending appeal, and the Supreme Court has accepted the case, with oral arguments beginning on November 5, 2025. Legal experts at a recent briefing warned that the outcome is highly unpredictable. On one hand, a court invalidating the tariffs could require the U.S. to refund billions in duties, with only the parties in the lawsuit guaranteed an “automatic” return. On the other hand, even a loss for the administration would leave the President with fallback powers: Section 338 of the 1930 Tariff Act authorizes the President to impose up to 50% duties on any country that “discriminates” against U.S. trade.

More fundamentally, experts note tension between presidential actions and Congressional authority. U.S. trade policy is traditionally Congress’s domain, and the Constitution requires legislative approval for binding international agreements. The administration’s use of Section 232 as a tool to address trade balances, and absence of formal Senate ratification, has been criticized as constitutionally dubious. Some argue that if the courts fully uphold this executive-led tariff regime, Congress would effectively be sidelined in setting trade policy. Conversely, a ruling against the government could force major changes in how import duties are imposed. In any event, the pending Supreme Court decision will have profound implications for the stability of U.S. tariff law and the balance of trade powers.

In summary, the United States has taken aggressive steps since to expand reciprocal tariffs on a wide range of imports, even as it has rolled back certain duties under the EU–U.S. trade agreement. These developments have introduced both new regulatory mechanisms and fresh legal uncertainty. European exporters now potentially face heavier tariffs on steel, auto parts, robotics, medical supplies, and more, reflecting the U.S. strategy of “balanced” trade measures. How this strategy coexists with the nascent EU–U.S. agreement – and how it will ultimately be judged by the courts – remains to be seen. What is clear is that, for the foreseeable future, transatlantic trade will be governed by a mix of negotiated tariff concessions and unilateral U.S. measures enforced through executive authority.