Victory disease

Victory disease occurs in military history when complacency or arrogance, brought on by a victory or a series of victories, makes an engagement end disastrously for a commander and his forces.

A commander may disdain the enemy, and believe his own invincibility, leading his troops to disaster. That commander may employ strategies that, if effective in earlier combats or maneuvers, prove catastrophic against a new or smarter enemy. The commander afflicted by "victory disease" may also fail to anticipate that a new enemy may use tactics different from those of old enemies. An overconfident commander may disregard military intelligence that would enable the commander to realize that new tactics are needed.

Though "victory disease" does not inevitably foretell defeat, it often precedes it. The term is also applied outside the military world.

The origin of the term ((戦勝病 senshoubyou) in Japanese is associated with the Japanese advance in the Pacific Theater of World War II, where, after attacking Pearl Harbor in 1941, Japan won a series of nearly uninterrupted victories against the Allies in Southeast Asia and the Pacific.

Although the Japanese had planned to establish a perimeter and go on the defensive, victories encouraged them to continue expanding to where it strained logistics and the navy. This culminated in the Battle of Midway in 1942, a catastrophic defeat of the Japanese navy: all four Japanese aircraft carriers involved were sunk, and the hitherto unstoppable Japanese advance was blunted.

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