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Tariffs and trade wars
· Law or rule
Fact, law or dataA rule, statute, definition or measured number.
Taxes on imported goods, paid at the border by the importing company and usually passed on, at least partly, to buyers.
See it on the Money & Finance map →How it works
A US importer pays the duty to Customs and Border Protection when goods arrive: a 25% tariff on a $100 part costs $25. The importer absorbs it, squeezes the foreign supplier, or raises prices. Tariffs shield domestic producers but raise costs for every buyer, including factories that use imported steel. Partners often retaliate, producing a trade war. Congress holds the tariff power but has delegated much of it to presidents. Before the 1913 income tax, tariffs supplied most federal revenue.
Why it matters
Tariffs reshuffle prices, profits and supply chains. For property owners they show up in construction and renovation bills: steel, aluminum, lumber, appliances and electrical gear.
Facts, rules and data
The Treasury reports customs receipts monthly. Studies of the 2018–19 tariffs, by Amiti, Redding and Weinstein and by Fajgelbaum and colleagues, found US buyers bore nearly the full cost.
Debates and risks
Whether targeted tariffs can rebuild strategic industries, such as chips or steel, at an acceptable cost is genuinely debated, even among free-trade economists.
Inside this (3)
Connections (4)
▸Comparative advantage and free trade (Ricardo) argues against most Tariffs and trade warsMainstream view
The connection
If each country gains by specializing and trading, a tariff that blocks imports makes the country poorer overall: consumers pay more, and resources shift into industries where it has less edge. Protected producers gain, but by less than buyers lose. Economists allow exceptions, such as national-security goods, infant industries, or tariffs as a bargaining threat.
When and why
From Ricardo's 1817 argument through Britain's 1846 repeal of its grain tariffs, the Corn Laws, and the postwar GATT rounds of tariff cuts.
How solid is the link?
In a 2018 Chicago Booth survey, none of the leading economists polled agreed that new US steel and aluminum tariffs would improve Americans' welfare.
Debates and risks
Whether strategic tariffs can protect critical supply chains, such as chips or medicines, at acceptable cost is a live debate, even among free traders.
▸Smoot–Hawley Tariff Act (1930) is the cautionary tale of Tariffs and trade warsFact, law or data
The connection
Smoot–Hawley became the textbook example of protectionism backfiring: higher duties, retaliation and shrinking trade during a slump. Its lesson led Congress in 1934 to let presidents negotiate tariff cuts with other countries, and shaped the postwar GATT. Opponents of new tariffs, including in 2025, still invoke it.
When and why
Washington, 1930; the Reciprocal Trade Agreements Act of 1934, under Franklin Roosevelt and Secretary of State Cordell Hull, began the reversal.
How we know
The 1934 act's history and decades of congressional and presidential speeches cite it directly; it is a fixture of economics textbooks.
Debates and risks
Some historians argue its reputation exceeds its actual effect, and that the real lesson concerns timing and retaliation more than tariffs as such.
▸US tariff surge of 2025–26 and the IEEPA ruling revived broad use of Tariffs and trade warsFact, law or data
The connection
After decades of falling US tariffs, the 2025 measures restored them as a central tool of economic policy, used for revenue, leverage over trading partners, and pressure on issues like migration and fentanyl. They raised the average effective US tariff rate to its highest level since the 1930s.
When and why
Washington, from February 2025, under President Trump; challenged in the Court of International Trade and decided by the Supreme Court in February 2026.
How we know
Executive orders, CBP tariff schedules and Treasury customs receipts document the scope; the Yale Budget Lab and others track the average rate.
Debates and risks
Whether tariffs stay this high after the court ruling and future elections, and whether Congress reasserts its constitutional tariff power, is unknown.
▸BRICS payment plans: BRICS Pay and linked national systems drew US threats of Tariffs and trade warsFact, law or data
The connection
In November 2024 Donald Trump, then president-elect, threatened 100% tariffs on BRICS countries if they created a currency to replace the dollar; in July 2025 he threatened an extra 10% on countries aligning with BRICS. The threats raised the political cost of payment plans for members like India and Brazil.
When and why
Social-media posts in November 2024 and July 2025, the latter during the Rio summit.
How we know
Trump's own posts and later White House statements.
Debates and risks
Whether the threats slowed BRICS plans or pushed members closer together.