Conversely, not every ongoing armed conflict is classified as a war.

Not all wars are formalized with official declarations of war between combatants. Countries subject to prolonged conflict can become war-torn countries that require many decades to rebuild their infrastructure, economy, and other functions. Often, countries' leaders become primary motivators of conflict by instigating a territorial dispute, trying to control another country's natural resources, or exercising authoritarian power over people. Among these are economic gain, territorial gain, religion, nationalism, civil war, and political revolution.

There are many possible reasons for war to begin between-or more often, within-nations. The Oxford English Dictionary defines 'war' as: (1) A state of armed conflict between different countries or different groups within a country (2) a state of competition or hostility between different people or groups, or (3) a sustained campaign against an undesirable situation or activity.

Armed conflict current armed conflicts