THE PRESIDENTIAL TARIFF POWER
The Constitution gives Congress authority over tariffs, but a century of delegation — Trade Expansion Act §232 (national security), Trade Act §301 (unfair practices), IEEPA (national emergency) — lets the president impose duties unilaterally. Trump's 2025 tariffs lean primarily on IEEPA, a 1977 statute originally designed for sanctions on hostile states.
WHY RATIFICATION IS HARD
EU trade deals technically fall under exclusive Commission competence, but anything touching investment protection or services becomes a 'mixed agreement' requiring all 27 national parliaments plus several regional ones. The EU-Canada CETA deal has been provisionally applied since 2017 and is still not fully ratified — Belgium's Walloon parliament alone held it up for years.
THE TRADE IMBALANCE
The US runs a goods deficit with the EU of roughly $200bn annually, but a services surplus of around $75bn. Counted together, the transatlantic relationship is closer to balance than the goods-only number suggests — a distinction Trump's tariff framing rejects.
THE STEEL & ALUMINUM CARVE-OUT
Steel and aluminum sit outside most trade frameworks because Section 232 treats them as national-security goods. Trump's first-term 25% steel and 10% aluminum tariffs (2018) hit EU exporters; Biden replaced them with tariff-rate quotas in 2021; Trump restored and raised them in 2025. The metals are the recurring sticking point because every administration treats them as strategic.
THE LEVERAGE ASYMMETRY
The EU exports about 20% of its goods to the US; the US sends roughly 18% of its exports the other way. But EU exports concentrate in higher-margin sectors — German autos, French luxury, Italian machinery — where US tariffs hit fewer firms harder. Retaliation tends to target politically symbolic American goods: bourbon, motorcycles, blue jeans — the 2018 EU response playbook.
THE WTO BACKDROP
The WTO's Appellate Body has been non-functional since 2019, when the US blocked judge appointments. Without a working dispute system, tariff disputes have no neutral arbiter — countries either negotiate bilaterally or retaliate unilaterally. The institutional vacuum is what makes deadlines like July 4 binding in practice.