Military Invasion

A Military invasion is the act of armed forces of one geopolitical entity entering territory controlled by another, generally with the intention of conquering the territory or altering the established government. Military invasions are often the cause or the result of war. They can be a single action or a part of a larger strategy to end a war, and they can be conducted in conjunction with other forms of conflict such as coups d’etat, civil wars, rebellions, guerrilla attacks and reconnaissance in force.

In the past, invasions were mounted for a variety of reasons including restoration of lost territory; religious idealism; policies of economic gain (such as the acquisition of natural resources); preempting a perceived attack from an enemy or potential threat to a polity’s territory; a desire to quell destabilizing warfare within or between neighboring polities; and a general sense of national interest. Today, if a polity conducts an invasion without being attacked first, it is considered to be an act of aggression and condemned by the international community.

To prevent a successful invasion, many governing bodies construct defensive structures such as castles and forts around borders or strategically located in the country. These can be spaced to slow down the advancing army, and they are often positioned in ways that block access to supplies or allow the defenders to shoot back into surrounding territory. Another method to impede an invader is by assassinating potentially threatening political or military figures, or by choking the supply lines that would be used to replenish supplies.