The Pearl Harbor force's indirect approach suggests a rough Japanese strike radius of about 4,000 nautical miles. The opening blow needed to create an emotional political reaction and lure the American fleet into an exposed advance rather than merely damage a base. Sinking ships at sea would remove hulls and crews more permanently than sinking them in harbour, where salvage was possible. These criteria show that the ideal target was a political trigger for fleet movement, rather than simply the place where Japanese aircraft could inflict the greatest immediate damage.
Chapter · 27:14-28:17
The target criteria: range, emotion, and ships at sea
Alternative targets are judged by carrier range, their power to provoke pursuit, and whether American ships could be sunk beyond salvage depth.