Two-Front War

Strategists have grappled with multi-front conflict since antiquity — Rome first faced this challenge in the 3rd century BCE, fighting Carthage in the Second Punic War while simultaneously waging the First Macedonian War. The strategic dilemma was formalized in German military doctrine with the Schlieffen Plan of 1905, which attempted to solve the problem of fighting France and Russia simultaneously. World War II made the concept famous in public consciousness, when Nazi Germany's simultaneous Western and Eastern fronts contributed to its defeat.