Why We Fight (2005) is a documentary film directed by Eugene Jarecki about the United States’s relationship with war. Its title is an allusion to the World War II-era newsreels of the same name, which were commissioned by the United States to justify their decision to go to war against the Axis Powers.

Why We Fight describes the rise and maintenance of the United States military-industrial complex and its involvement in the wars led by the United States during the last fifty years, and in particular in the 2003 Invasion of Iraq. The film alleges that in every decade since World War II, the American public has been told a lie to bring it into war to fuel the military-economic machine, which in turn maintains American dominance in the world.