If the US Fleet had sailed toward the Philippines on 5 or 6 December 1941, could Kido Butai have chased it and still returned home?
Short answerIt had the fuel capacity in principle, but only timely intelligence made the pursuit plausible; delay and high-speed fuel consumption would quickly turn it into a losing tail chase.
NotesIn this counterfactual, Kido Butai had enough fuel in principle to attempt a pursuit toward the Philippines. Sustained high speed would consume that margin rapidly, so the force needed early intelligence that the US Fleet had sailed. A report received only on 7 December would leave the carriers in a long tail chase against a force already well ahead. If the absence were discovered only during the Pearl Harbor strike, the chance to redirect effectively would have passed.