The Maginot Line was a significant defensive fortification built by France along its border with Germany after World War I, intended to deter German aggression during World War II. It symbolized France's strategy of defense through fortifications rather than rapid mobilization and offense. However, during the war, the Germans bypassed the line by invading through Belgium, highlighting the limitations of static defensive structures. The failure of the Maginot Line to prevent invasion contributed to France's swift defeat in 1940 and underscored the changing nature of warfare, where mobility and rapid movement became essential.