CEVAP:

Balance-of-power is a major concept in classical realism and in contemporary  eorealism. In general, balance-of-power theory holds that an extreme concentration of material power in the hands of single state or attempts by a state to conquer a region will provoke countervailing actions. These countervailing actions, called balancing, can take the form of alliance formation (external balancing) or efforts by individual states to increase their own relative power, generally through arms racing and military innovation (internal balancing). While balancing does not always operate efficiency to prevent the outbreak of war, it does help to maintain the stability of relations among states in the long-term.