Mercantilism

Definitions
1. from the 16th to the 19th centuries, a system of government-sponsored international business ventures designed to make European monarchs rich.
2. an economic theory that holds the prosperity of a state as dependent upon its supply of capital, that the global volume of international trade is "unchangeable," and that one party may benefit only at the expense of another. -wikipedia.org
Explanation
When one country starts to benefit due to when another country has expenses.
Metaphor
Mercantilism is like monopoly. Everyone wants to own the most land and money, and likes when the other players have to pay them more money and start to go bankrupt. they are gaining from others expenses.