Comparative Advantage and the Gains from International Trade – Chapter 9 Study Notes

Comparative Advantage and the Gains from International Trade

9.1 The United States in the International Economy

International trade has become increasingly important to the U.S. economy over the past 50 years, driven by reduced shipping, transportation, and communication costs. Governments have also facilitated trade by changing policies.

• Tariff: A tax imposed by a government on imports.

• Imports: Goods and services bought domestically but produced in other countries.

• Exports: Goods and services produced domestically but sold in other countries.

• Historically, high tariffs on imports were used to protect domestic industries, but this also led to similar taxes on exports.

Example: Figure 9.1 shows that from 1970 to the late 2000s, imports and exports rose as a fraction of U.S. GDP, highlighting the growing importance of international trade. The Great Recession caused a decline, but trade remains significant.

9.2 Comparative Advantage in International Trade

Comparative advantage is a foundational concept in international trade, explaining why countries benefit from trading even if one is more productive in all areas.

• Comparative advantage: The ability to produce a good or service at a lower opportunity cost than competitors.

• Absolute advantage: The ability to produce more of a good or service than competitors using the same amount of resources.

• Opportunity cost: The highest-valued alternative that must be given up to engage in an activity.

Example: Table 9.1 shows U.S. workers have an absolute advantage in producing both smartphones and wheat compared to Chinese workers.

	Output per Hour of Work Smartphones	Output per Hour of Work Wheat (bushels)
China	4	2
United States	6	12

However, Table 9.2 demonstrates that comparative advantage depends on opportunity costs:

	Opportunity Costs Smartphones	Opportunity Costs Wheat (bushels)
China	0.5 bushel of wheat	2 smartphones
United States	2 bushels of wheat	0.5 smartphone

Autarky is a situation where a country does not trade with others; relative prices reflect opportunity costs.

9.3 How Countries Gain From International Trade

Countries gain from trade by specializing in goods for which they have a comparative advantage and trading for others.

• Without trade, countries consume only what they produce.

• With trade, both countries can be better off by exchanging goods they produce efficiently for those produced efficiently by others.

Example: Table 9.3 shows production without trade:

	Production and Consumption Smartphones	Production and Consumption Wheat (bushels)
China	1,000	1,500
United States	1,500	9,000

Specialization according to comparative advantage increases total output:

	Smartphones	Wheat
China	4,000	0
United States	0	12,000

Terms of trade is the ratio at which countries exchange exports for imports. Acceptable terms must be better than a country's opportunity cost.

	Production with Trade	Trade	Consumption with Trade
China	4,000 smartphones, 0 wheat	-1,500 smartphones, +1,500 wheat	2,500 smartphones, 1,500 wheat
United States	0 smartphones, 12,000 wheat	+1,500 smartphones, -1,500 wheat	1,500 smartphones, 10,500 wheat

Both countries consume more than they could without trade.

Why Don’t We See Complete Specialization?

Complete specialization is rare due to:

• Not all goods/services are tradable internationally (e.g., medical services).

• Increasing opportunity costs in production.

• Differing tastes for products across countries.

Does Anyone Lose as a Result of International Trade?

While trade benefits countries overall, some individuals and firms may lose:

• Chinese wheat farms and workers

• U.S. smartphone firms and workers

These groups may seek protectionist policies such as tariffs and quotas.

Where Does Comparative Advantage Come From?

• Climate and natural resources: Some nations are better suited for certain types of production (e.g., bananas in Costa Rica, wheat in the U.S.).

• Relative abundance of labor and/or capital: Nations differ in the availability of skilled/unskilled labor and infrastructure (e.g., China vs. U.S.).

• Technological differences: Technologies may not diffuse quickly or uniformly (e.g., U.S. excels in product technologies, Japan in process technologies).

• External economies: Cost reductions from industry size (e.g., Silicon Valley, Hollywood).

9.4 Government Policies That Restrict International Trade

Governments may restrict trade to protect domestic industries, even if those industries lack comparative advantage.

• Income is higher when specializing in goods with comparative advantage.

• Political pressure often leads to protectionist policies.

Example: U.S. market for ethanol under autarky vs. free trade:

• Under autarky, domestic production meets all demand; consumer and producer surplus are determined by domestic prices.

• With free trade, imports lower prices, benefiting consumers but harming domestic producers.

Tariffs: Taxes on imports; Quotas/VERs: Limits on import quantity.

Effects of Tariffs and Quotas

Tariffs and quotas raise domestic prices, increase producer surplus, and reduce consumer surplus, often resulting in deadweight loss.

Policy	Effect on Price	Effect on Producer Surplus	Effect on Consumer Surplus	Deadweight Loss
Free Trade	Lower	Lower	Higher	None
Tariff	Higher	Higher	Lower	Present
Quota	Higher	Higher	Lower	Present

Example: U.S. sugar quota raises prices, benefits producers, but costs consumers billions annually.

9.5 The Debate over Trade Policies and Globalization

Trade policies and globalization are debated due to their economic and cultural impacts.

• Economists generally favor freer trade for overall national benefit.

• Opposition arises from concerns about job losses, wage protection, infant industries, and national security.

• Globalization can lead to cultural changes and perceived unfairness due to regulatory differences.

World Trade Organization (WTO): Oversees international trade agreements and dispute resolution.

Additional info:

• Dumping refers to selling products below cost; WTO allows anti-dumping measures, though determining true costs is complex.

• Positive analysis describes "what is"; normative analysis describes "what ought to be." Trade policy debates often involve both.

• Political economy: Benefits of trade restrictions are concentrated among a few, while costs are spread across many, influencing policy decisions.

• Building bridges (e.g., retraining, tax credits) can help those negatively affected by trade.