Midway carrier losses and air-group attrition

The Midway losses cannot be reduced to one design flaw. A carrier built to keep enemies at range is acutely vulnerable when found with fueled and armed aircraft aboard. Concealment, movement, and a layered escort can reduce that danger, but no defensive system is infallible once an attacker locates the carrier. Sōryū's hits triggered secondary explosions and rapidly uncontrollable fires, while Hiryū was struck forward, lost flight-deck function, and burned badly enough that attackers shifted targets. Hiryū initially retained propulsion and remained afloat long after abandonment and Japanese torpedo attempts, showing that loss of aviation function and loss of buoyancy were different thresholds. The strategic cost extended beyond the hulls because the loss of aviators, maintainers, and carriers eroded the capability Japan had built up.