Member of an irregular military force fighting small-scale, fast-moving actions, usually in concert with an overall political-military strategy, against conventional military and police forces. Guerrilla tactics involve constantly shifting attacks, sabotage, and terrorism. The word (the diminutive of the Spanish guerra, “war”) was first used to describe Spanish-Portuguese irregulars who helped drive Napoleon's French army from the Iberian Peninsula in the early 19th century. The strategy of the guerrilla is to wear down the enemy until he can be defeated in conventional battle or to subject him to so much military and political pressure that he sues for peace. The Chinese general Sunzi (5th century BC) was one of the first to write down the theories of guerrilla warfare.
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