Trade theories from the past, like mercantilism and comparative advantage, have greatly influenced how countries interact today, especially when it comes to trade and economic agreements.

1. Mercantilism:

   • This idea focuses on a government controlling the wealth of a country.
   • It values having more exports than imports, which means selling more to other countries than buying from them.
   • This approach helped boost colonialism, where countries expanded their territories to gain more resources.

2. Comparative Advantage:

   • This theory was introduced by David Ricardo.
   • It suggests that countries should focus on what they do best and trade for the rest.
   • This idea has led to more interconnected economies around the world. A 2019 report from the World Trade Organization (WTO) showed that global merchandise trade reached $19 trillion.

3. Modern Implications:

   • Groups like the WTO were created to help manage and oversee trade.
   • Trade agreements, like NAFTA, affect around 500 million people and involve $1.3 trillion in goods every year.

Trade theories still play an important role in how countries deal with each other economically and diplomatically.