Macroeconomics guide, Unit 7, step 21 of 23Previous step Next step

Step 21: Trade Protection and Economic Integration

By the EconTutorials team. 10-minute read with 6 practice questions.

SyllabusCambridge 6.2, 11.6 · IB 4.2–4.4

In 30 seconds

Protection means government measures that restrict imports: tariffs, quotas, subsidies to domestic producers, embargoes and administrative barriers.
A tariff raises the domestic price, increases domestic output, cuts imports, raises government revenue and creates a deadweight loss.
Trading blocs deepen step by step: preferential agreement → free trade area → customs union → common market → monetary union.
Joining a bloc can cause trade creation (good) or trade diversion (bad). Exams reward you for weighing up both.

Video lesson coming soonA short animated lesson for this step will appear here.

What protection means

Imagine a local bicycle maker. Imported bikes sell for $100, but the local firm needs $120 to make one, so customers buy imports. If the government puts a $25 tax on every imported bike, imports cost $125 and the local $120 bike looks competitive. That tax is a tariff, and the government has protected a domestic industry.

Key termProtectionism: government policies that restrict international trade to shield domestic producers from foreign competition.

Types of protection

Tariff: a tax on imported goods. It raises the price of imports and earns revenue for the government.
Quota: a physical limit on the quantity of a good that can be imported, for example no more than 10,000 cars a year. The domestic price rises, but there is no tariff revenue; the extra profit goes to whoever holds the import licences (unless the government auctions them).
Subsidy to domestic producers: a government payment that lowers domestic firms’ costs, so they can sell at the world price and produce more. Consumers still pay the world price, but taxpayers fund the subsidy.
Embargo: a complete ban on trade with a country or in a product, usually for political reasons.
Administrative barriers: red tape that makes importing harder, such as strict product standards, slow customs checks, complex licensing or “buy local” rules for government purchases.

How a tariff works: the diagram and the numbers

DiagramDraw a domestic market with price on the vertical axis and quantity on the horizontal axis. Draw domestic demand (D, sloping down) and domestic supply (S, sloping up). Draw a horizontal world price line $ P_w $ below the point where D and S cross. At $ P_w $, domestic firms supply $ Q_1 $ and consumers buy $ Q_4 $; the gap $ Q_4 – Q_1 $ is imports. Now draw a second horizontal line higher up at $ P_w + t $, where $ t $ is the tariff. At the new price, domestic supply rises to $ Q_2 $, demand falls to $ Q_3 $, and imports shrink to $ Q_3 – Q_2 $. Shade four areas: (1) the gain in producer surplus to the left of S between the two price lines; (2) a triangle between S and the price lines from $ Q_1 $ to $ Q_2 $ — lost efficiency from high-cost domestic production; (3) the rectangle $ t \times (Q_3 – Q_2) $ — tariff revenue; (4) a triangle between D and the price lines from $ Q_3 $ to $ Q_4 $ — lost consumption. Areas (2) and (4) together are the deadweight loss.

Worked example

For example, a country’s demand for shoes is $ Q_d = 120 – 4P $ and its domestic supply is $ Q_s = 4P – 20 $ (Q in thousands of pairs, P in dollars). The world price is $10. The government imposes a $2 tariff. Find imports before and after, the tariff revenue and the deadweight loss.

Step 1$ P = 10: \; Q_d = 120 – 40 = 80, \; Q_s = 40 – 20 = 20, \; \text{imports} = 80 – 20 = 60 $

Step 2$ P = 12: \; Q_d = 120 – 48 = 72, \; Q_s = 48 – 20 = 28, \; \text{imports} = 72 – 28 = 44 $

Step 3$ \text{Tariff revenue} = 2 \times 44 = 88 \text{ (thousand dollars)} $

Step 4$ \text{DWL} = \tfrac{1}{2}(2)(28 – 20) + \tfrac{1}{2}(2)(80 – 72) = 8 + 8 = 16 $

The tariff cuts imports from 60,000 to 44,000 pairs and raises $88,000 for the government. Consumers lose surplus of $ 2 \times 72 + \tfrac{1}{2}(2)(8) = 152 $ thousand dollars, producers gain $ 2 \times 20 + \tfrac{1}{2}(2)(8) = 48 $, and the government gains 88. Since $ 152 – 48 – 88 = 16 $, the country as a whole loses $16,000: the deadweight loss.

Arguments for and against protection

Arguments for

Infant industry: a new industry may have high costs until it grows large enough to gain economies of scale. Temporary protection lets it grow up before facing full competition.
Strategic industries: some industries matter for national security or survival, such as food, energy, steel or defence equipment, so a country may not want to rely on imports.
Anti-dumping: dumping means a foreign firm selling exports at a price below its cost of production, or below the price in its home market. Tariffs can stop this unfair competition.
Protecting employment: limiting imports may save jobs in industries facing strong foreign competition, especially in regions with few other jobs.
Government revenue: tariffs are easy to collect at the border, which matters for low-income countries with weak income-tax systems.

Arguments against

Retaliation: other countries may put tariffs on your exports, leading to a trade war in which everyone loses.
Inefficiency: protected firms face less competition, so they have weaker incentives to cut costs and innovate. Resources stay in high-cost industries instead of moving to where the country has a comparative advantage.
Higher prices and less choice: consumers pay more, and firms that use imported inputs face higher costs, making them less competitive.
Deadweight loss: as the worked example shows, total welfare falls.
Infant industries may never “grow up”, and temporary protection often becomes permanent through lobbying.

Common mistakeSaying a quota raises government revenue. A quota restricts quantity; the higher price creates extra profit for licence holders or foreign exporters, not tax revenue, unless the government sells the licences. Only a tariff automatically raises revenue.

The World Trade Organization

The World Trade Organization (WTO), set up in 1995 to replace the GATT, is the international body that sets the rules of world trade. It:

runs negotiations to reduce tariffs and other barriers;
applies the most-favoured-nation principle: a country must normally offer every WTO member the same low tariff it offers its best trading partner (trading blocs are an allowed exception);
settles trade disputes between member countries;
allows some protection, such as anti-dumping duties, under agreed rules.

Trading blocs: levels of economic integration

A trading bloc is a group of countries that agree to reduce trade barriers between themselves. Think of it as a ladder: each step includes everything on the step below, plus something more.

Level	What members agree	Example
Preferential trade agreement	Lower (not zero) tariffs on some goods traded between members	Many bilateral agreements between pairs of countries
Free trade area	No tariffs between members; each member keeps its own tariffs against outsiders	USMCA (United States, Mexico, Canada), which replaced NAFTA
Customs union	Free trade between members plus a common external tariff against non-members	The EU customs union; the GCC customs union
Common market	Customs union plus free movement of labour and capital	The EU single market; the GCC common market
Monetary union	Common market plus a single currency and a single central bank	The eurozone (euro, European Central Bank)

A free trade area needs rules of origin: because members keep different external tariffs, outsiders could ship goods through the lowest-tariff member. A customs union avoids this with one common external tariff.

A monetary union removes exchange-rate risk, but members give up their own interest rate and exchange rate, even when one is booming and another is in recession.

Trade creation and trade diversion

Key termTrade creation: when joining a bloc shifts purchases from a higher-cost domestic producer to a lower-cost producer in a partner country. Trade diversion: when joining a bloc shifts purchases from a lower-cost producer outside the bloc to a higher-cost producer inside it.

Worked example

For example, Country H imports cars. Japan can supply a car for $20,000 and Germany for $22,000. H charges a 20% tariff on all imported cars. H then joins a customs union with Germany. Which country does H buy from, before and after?

Step 1$ \text{Before: Japan } = 20\,000 \times 1.2 = \$24\,000; \; \text{Germany } = 22\,000 \times 1.2 = \$26\,400 $

Step 2$ \text{H buys from Japan at } \$24\,000 \text{ (government gets } \$4\,000 \text{ tariff)} $

Step 3$ \text{After: Germany (no tariff) } = \$22\,000; \; \text{Japan still } = \$24\,000 $

Step 4$ \text{H now buys from Germany, paying } 22\,000 – 20\,000 = \$2\,000 \text{ more per car in real cost} $

This is trade diversion. Consumers pay $2,000 less per car than before ($22,000 instead of $24,000), but the government loses $4,000 of tariff revenue per car, and the country now pays a less efficient producer. Had H’s own car makers produced at, say, $23,000 before the union (beating both taxed imports), switching to German cars at $22,000 would instead be trade creation: a gain, because a cheaper producer replaces a dearer one.

A bloc helps when trade creation outweighs trade diversion: more likely when the common external tariff is low, members already trade heavily, and the larger market brings economies of scale and competition (the dynamic benefits).

Globalisation: costs and benefits

Globalisation is the growing integration of the world’s economies through trade, capital flows, migration and technology.

Benefits	Costs
Countries specialise by comparative advantage, raising world output	Workers in industries that lose out to imports may face unemployment
Lower prices and more choice for consumers	Income inequality may widen within countries
Economies of scale from selling to bigger markets	Dependence on others: a shock in one country spreads quickly
Foreign direct investment brings capital, jobs and technology	Environmental damage from more production and transport
Faster spread of ideas and technology	Loss of national control and the power of large multinational firms

Exam tipCambridge 9708: for a tariff question, draw the world-price diagram and identify each area (revenue, producer gain, deadweight loss) by letter, then explain. For “discuss” or “assess” questions on protection or blocs, give arguments on both sides, use the trade creation/diversion distinction by name, and reach a justified conclusion (“it depends on whether…”). IB Paper 1 and 2: use real-world examples such as USMCA, the EU or the GCC, and evaluate effects on different stakeholders: consumers, domestic producers, workers, the government and foreign producers.

Practise: 6 questions

Try each one on paper first, then check the worked answer.

EasyQ1. A government puts a $3 tariff on each imported phone case. After the tariff, 500 cases are imported. How much tariff revenue does it collect? Show worked answer

Revenue = tariff × imports after the tariff = $3 × 500 = $1,500.

EasyQ2. Name the level of integration: (a) members share free trade and a common external tariff, but workers cannot move freely; (b) members share a currency and a central bank; (c) members remove tariffs between themselves but keep their own tariffs against others. Show worked answer

(a) Customs union.
(b) Monetary union.
(c) Free trade area.

MediumQ3. Demand is $ Q_d = 200 – 10P $ and domestic supply is $ Q_s = 10P – 20 $. The world price is $8. A $2 tariff is imposed. Calculate imports before and after, tariff revenue and deadweight loss. Show worked answer

At P = 8: Qd = 200 − 80 = 120; Qs = 80 − 20 = 60; imports = 60.
At P = 10: Qd = 200 − 100 = 100; Qs = 100 − 20 = 80; imports = 20.
Revenue = 2 × 20 = $40.
Deadweight loss = ½ × 2 × (80 − 60) + ½ × 2 × (120 − 100) = 20 + 20 = $40.

MediumQ4. Country K buys televisions. China can supply one for $300 and Mexico for $330. K charges a 25% tariff on all imports. K then forms a free trade area with Mexico. Is this trade creation or trade diversion? Show your working. Show worked answer

Before: China = 300 × 1.25 = $375; Mexico = 330 × 1.25 = $412.50. K buys from China.
After: Mexico = $330 (no tariff); China still = $375. K switches to Mexico.
K now buys from a higher-cost producer ($330 instead of $300), so this is trade diversion. Consumers pay $45 less per TV, but the government loses $75 of tariff revenue per TV, and the real cost to the country rises by $30 per TV.

MediumQ5. Explain the infant industry argument and give one reason why it may fail. Show worked answer

A new industry starts with high average costs because it is small. Temporary protection lets it expand and gain economies of scale and experience, until its costs fall enough to compete with established foreign firms; the protection can then be removed.
It may fail because protected firms lack the pressure of competition to become efficient, and owners and workers lobby to keep the protection, so the industry never “grows up” and consumers keep paying higher prices.

ExamQ6. Discuss whether a country benefits from joining a customs union. [8 marks] Show worked answer

Knowledge [2]: a customs union removes tariffs between members and sets a common external tariff against non-members.
Analysis for [2]: trade creation, as imports from lower-cost partners replace dearer domestic production, lowering prices and raising consumer surplus; dynamic gains from a larger market: economies of scale, more competition, more foreign direct investment.
Analysis against [2]: trade diversion, as imports switch from low-cost outsiders to higher-cost partners, and tariff revenue is lost; the country loses the freedom to set its own tariffs and trade deals; domestic firms may close when facing partner competition.
Evaluation [2]: the net effect depends on whether trade creation exceeds trade diversion, which is more likely if the common external tariff is low and members already trade heavily with each other. A justified conclusion, e.g. a small economy whose main partners are inside the union is likely to gain overall, but one that mainly buys from outside the bloc may lose.

Check yourself

1. Which form of protection automatically raises revenue for the government?

A tariff is a tax on imports; a subsidy costs the government money.

2. What does a customs union have that a free trade area does not?

Both remove internal tariffs; only a customs union sets one tariff against outsiders.

3. After joining a bloc, a country switches from a cheap non-member supplier to a dearer member supplier. This is:

Trade moves to a higher-cost producer only because of the bloc’s tariff advantage.

Your score: 0 out of 3

The short version

Tariffs, quotas, subsidies, embargoes and administrative barriers all protect domestic producers by restricting imports.
A tariff raises the price, increases domestic output, cuts imports, earns revenue and causes a deadweight loss.
Arguments for protection include infant industries, strategic industries, anti-dumping, jobs and revenue; against are retaliation, inefficiency and higher prices.
Integration deepens from preferential agreements to free trade areas, customs unions, common markets and monetary unions; the WTO sets the rules of world trade.
Blocs help when trade creation outweighs trade diversion; globalisation brings efficiency gains but also job losses, inequality and environmental costs.