# Seven Questions About Tariffs That Everyone Should Know Source: https://www.youtube.com/watch?v=N2zN4x5aEos Recap page: https://rapidrecap.app/video/N2zN4x5aEos Generated: 2026-02-20T14:35:46.692+00:00 --- ## Quick Overview Economists generally view tariffs as distortionary, causing welfare loss by creating a wedge between world prices and domestic prices, similar to introducing a crude instrument like acupuncture with a fork instead of targeted subsidies or taxes; however, tariffs can potentially improve welfare if they correct pre-existing market distortions, redistribute income domestically or internationally (optimal tariff argument), or if the world cannot absorb the tariff through price adjustments. **Key Points:** - US average tariffs were historically high until the post-WWII period, dropping to about 2% pre-2018, before rising to 4%-5% following the 2018 tariffs, and reaching heights not seen since the Great Depression (peak 20% in 1930) with recent statutory rates reaching up to 140% on some Chinese imports. - The standard economic case against tariffs highlights that they create two distortionary triangles: a production distortion where domestic production uses a higher-cost technology than importing, and a consumption distortion where consumers buy less because the tariff-inclusive price exceeds the true marginal cost (world price). - Tariffs can act as a second-best instrument to correct existing distortions, such as knowledge spillovers or imperfect competition, by incentivizing firms to produce more, although this is inefficiently bundled with a consumption tax, making targeted instruments like production subsidies superior ('acupuncture with a fork'). - Tariffs can function as a redistribution tool, either domestically (affecting producers vs. consumers, or different worker groups) or internationally through terms of trade manipulation (the optimal tariff argument), where the resulting welfare effects are first-order rectangles, unlike the second-order welfare losses from distortions (triangles). - Empirical analysis of the 2018-2019 trade war showed complete pass-through of tariffs at the border (price inclusive of tariff moved one-for-one with the tax), suggesting foreigners did not pay; furthermore, retail prices remained surprisingly stable, implying the cost was absorbed by retailers' profit margins, indicating potential domestic redistribution away from retailers. - Research suggests that in a realistic setting with limited redistribution instruments (like only income taxes besides tariffs), tariffs may be used as 'predistribution' to affect earnings distribution, and in this context, free trade is not necessarily optimal. - The argument that global tariffs are unfair because the US faces higher average tariffs than it imposes (US faces 3.5% vs. imposes 2% on average pre-2018) shows a qualitative asymmetry, but the magnitudes are small compared to potential gains from international redistribution via optimal tariffs. **Context:** Arnaud Costinot presents an analysis based on joint work with Andrés Rodríguez-Clare, addressing seven key questions about the normative effects of tariffs—whether they are good or bad and how to use data to determine their impact. The discussion begins with a historical overview of US tariff rates, tracing their decline after World War II, the spike during the Great Depression, and the recent sharp increase starting in 2018, before moving into theoretical frameworks explaining the gains from trade and the welfare costs associated with imposing tariffs. ## Detailed Analysis Costinot details the historical trajectory of US tariffs, noting they were nearly 90% of federal receipts before domestic taxes were introduced, peaked at 20% in the 1930s, fell to 2% pre-2018, and then rose significantly due to actions targeting China, reaching statutory heights unseen since the 1930s, although applied tariffs were often lower due to exemptions. Theoretically, free trade is analogous to technological progress, generating welfare gains represented by triangles in a partial equilibrium diagram because it lowers the effective marginal cost of goods via the lower world price (P*). Tariffs introduce a wedge (P* + tariff), creating two welfare-reducing distortions: production distortion (incentivizing higher-cost domestic production) and consumption distortion (reducing consumption below the efficient level). However, tariffs can be justified as a second-best instrument if pre-existing market failures (like knowledge spillovers or geopolitical externalities) make output too small; in this case, the tariff incentivizes production, generating a welfare gain triangle, though a targeted subsidy is superior. Furthermore, tariffs can serve a redistribution motive, either domestically (shifting income between producers and consumers) or internationally, where the optimal tariff argument suggests a country can improve its terms of trade by imposing a tariff, transferring welfare from foreigners to domestic agents, provided the rest of the world does not retaliate symmetrically, which leads to a Prisoner's Dilemma where all countries impose tariffs and end up worse off than under free trade, justifying rule-based systems like the WTO. Analyzing the 2018-2019 trade war data, researchers found complete pass-through of the tariff into US border prices (P* + t), meaning foreigners largely did not pay, and retail prices remained stable, suggesting the cost was initially absorbed by retailer profit margins, which implies domestic redistribution away from retailers rather than international transfers. ### Historical US Tariff Trends - Tariffs accounted for 90% of federal receipts pre-1860 - Tariffs declined post-WWII to 2% pre-2018 - Recent tariffs elevated the average rate to 4%-5%, with some specific rates reaching 140%. ### Standard Case Against Tariffs - Trade is like technological progress, lowering costs via world price P* - Tariffs create production and consumption distortions summarized by welfare-loss triangles - Distortions mean the wedge prevents efficient resource allocation. ### Tariffs as Second-Best Instruments - Tariffs correct pre-existing distortions (e.g., knowledge spillovers) where social marginal cost differs from private marginal cost - This use is compared to 'acupuncture with a fork' because it distorts consumption while fixing production. ### Redistribution and Optimal Tariff Argument - Tariffs create first-order redistribution effects (rectangles) distinct from second-order efficiency losses (triangles) - International redistribution occurs if the imposing country has market power, lowering import prices (P*) and benefiting the imposing nation at the expense of foreigners. ### Empirical Findings from 2018-2019 Trade War - Border prices (P* + t) moved one-for-one with the tariff, showing complete pass-through, meaning US importers/consumers paid - Retail prices remained stable, implying profit margins of retailers absorbed the cost, suggesting domestic redistribution towards retailers. ### The Prisoner's Dilemma of Protectionism - Unilateral incentives lead countries to impose tariffs to improve terms of trade (international transfer) - Symmetric retaliation results in a Nash equilibrium where all countries are worse off due to distortions canceling out transfer benefits.