Key point: The Battle of Guadalcanal was a major victory for American morale.
Both sides needed reinforcements. For the Japanese and the Americans in October 1942, the battle for Guadalcanal was turning into a bottomless pit, demanding more and more scarce resources—in the air and at sea and, most importantly, on the ground. Control of the malarial, jungle-clad island and its airfield might determine the fate of the war in the Pacific.
The problem was that neither the Japanese nor the Americans had the resources. Both nations were trying to wage the South Pacific war on the cheap—the bulk of Japan’s ground forces were committed to the endless war in China, and the United States was committed to the “Germany First” policy, which made the war in Europe the first priority. Both sides lacked troops, transports, planes, and basic supplies.
Nevertheless, as the U.S. Marines and Japanese Army units on Guadalcanal became exhausted from heavy combat and rugged conditions, it was more imperative than ever to resupply and reinforce the troops—on both sides.
As September turned to October, the Japanese moved first. The local commander, Rear Admiral Gunichi Mikawa, using destroyer transports, ordered the delivery of 10,000 men of the tough 2nd Infantry Division to Guadalcanal’s Cape Esperance in eight nocturnal runs down the channel between the Solomon Islands chain, a route known to the Americans as The Slot, in a measure the Japanese called the Ant Transportation, but known to Americans then and forever as the Tokyo Express.
The Americans did not waste time in reacting. Admiral Chester Nimitz, Commander-in-Chief Pacific, ordered his top sailors on the scene to take swift action.