Could Kido Butai have sunk the American battle line if it had sortied after a warning?
Short answerIt might sink some ships if it found them, but a maneuvering, battle-ready fleet would be harder to locate and less vulnerable.
NotesThe outcome depends on where the fleet sailed, whether it joined the carriers, and whether Japanese searches found it. Ships underway would be closed up for action, manoeuvring, and able to use their guns without concern for shore installations. Even if Kido Butai located them, those conditions would probably reduce the number of battleships lost compared with ships caught alongside. A position southeast or southwest of Oahu would put the battle line farther from the Japanese approach. Aircraft based at Pearl Harbor could then search for the enemy while the fleet remained in that less exposed position.