Why might a balance of power prevent war

when balance of power exist between two nations, all the countries that are involved in a conflict would be fully aware that each of them had the capability to create massive destruction toward one another.

Because of this awareness, both parties would become hesitant in making initiation to start a war and might choose diplomatic method to solve their difference.

Nobody will feel the need to start war.

Explanation:

Sometimes one will start war as an act of self defenses, if everybody is equal there is no reason to feel threatened by another.

then your answer is a

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