Balance of power is a system of maintaining peace through an even distribution of military and economic power among nations or groups of nations. It was an important principle of international relations from the 1500’s to the 1900’s. Countries achieved a balance of power by forming alliances so that no nation or alliance was strong enough to take over.
A balance of power system must have at least three powerful countries. If any nation gains too much power, the others form an alliance against it. In most cases, each member of an alliance agrees to defend any other member that is under attack. The strength of the alliance discourages attacks. During the early 1900’s, for example, a balance of power existed between the six chief powers of Europe. Germany, Austria-Hungary, and Italy belonged to a group called the Triple Alliance, which opposed a group called the Triple Entente, consisting of the United Kingdom, France, and Russia.
A balance of power requires that nations be willing to form alliances with any country despite differences in political beliefs or goals. Such alliances may be short-term agreements. The nations involved usually build up their military and economic strength so no other nation can achieve an overwhelming military advantage. If one of the major nations is weakened by war, the entire balance of power system may collapse.
Bipolar and multipolar systems differ from a balance of power system. In a bipolar system, there are two major nations and most other countries side with one of the two. In a bipolar system, none of the countries can serve as power balancers. A multipolar system includes more than three major nations, each acting independently rather than in an alliance.
