Explain the gains from international trade using the theory of comparative advantage.

What this dot point is asking

You need to explain absolute and comparative advantage, show how specialisation and trade produce gains, and identify the main barriers to trade and the case for and against free trade.

Absolute versus comparative advantage

• Absolute advantage exists when a country can produce more of a good than another using the same resources.
• Comparative advantage exists when a country can produce a good at a lower opportunity cost than another, meaning it gives up less of other goods to do so.

Comparative advantage, not absolute advantage, is the basis for beneficial trade. Even a country that is more efficient at producing everything still gains by specialising in what it produces relatively best and importing the rest.

How specialisation creates gains from trade

If each country specialises in the good in which it has a comparative advantage and trades for the rest, total output rises and both countries can consume beyond their own production possibility frontier.

Why countries restrict trade

Despite the gains, governments often restrict trade using:

• Tariffs - taxes on imports that raise their price and protect domestic producers.
• Quotas - limits on the quantity of a good that can be imported.
• Subsidies - payments to domestic producers to lower their costs.
• Embargoes and standards - bans or regulatory hurdles.

Arguments for protection include defending infant industries, saving jobs, national security and preventing dumping. Arguments against include higher prices for consumers, inefficiency, retaliation by trading partners, and the loss of the gains from specialisation.

Free trade and Australia

Australia has reduced trade barriers over recent decades and signed many free trade agreements. Free trade exposes domestic firms to competition, lowers prices, widens consumer choice and lets Australia specialise in areas of comparative advantage such as minerals, energy and agriculture. The trade-off is structural adjustment, as some protected industries shrink and workers must move to growing sectors.

Why this matters

Comparative advantage is the foundation for understanding globalisation. It explains the pattern of Australia's exports and imports, why free trade agreements are pursued, and why protectionism, though politically popular, usually reduces overall welfare. It links directly to exchange rates and the balance of payments in the next dot point.