A more thorough explanation:

Definition: Trading with the enemy is a federal crime that involves conducting business with a country or its citizens that the United States is at war with.

Example: During World War II, it was illegal for American companies to sell goods to Germany or Japan. If a company was caught doing so, they could be charged with trading with the enemy.

Explanation: This example illustrates how trading with the enemy works. When a country is at war with another country, it is illegal to conduct business with that country or its citizens. This is because the goods or services provided could be used to support the enemy's war effort, which would harm the United States and its allies.