severe destruction in the three nights between 13 and 16 October. However, the Battle of Cape Esperance provided a significant morale boost to the U.S. Navy after its disastrous defeat at the Battle of Savo Island. Background On 7 August 1942, Allied forces (primarily U.S.) landed on Guadalcanal, Tulagi, and Florida Islands in the Solomon Islands. The objective was to deny the islands to the Japanese as bases for threatening the supply routes between the U.S. and Australia, and secure starting points for a campaign to isolate the major Japanese base at Rabaul while also supporting the Allied New Guinea campaign. The Guadalcanal campaign would last six months. Taking the Japanese by surprise, by nightfall on 8 August, the Allied forces, mainly consisting of U.S. Marines, had secured Tulagi and nearby small islands, as well as an airfield under construction at Lunga Point on Guadalcanal (later completed and named Henderson Field). Allied aircraft operating out of Henderson became known as the "Cactus Air Force" (CAF) after the Allied codename for Guadalcanal. In response, the Japanese Imperial General Headquarters assigned the Imperial Japanese Army's 17th Army—a corps-sized formation headquartered at Rabaul under Lieutenant-General Harukichi Hyakutake—with the task of retaking Guadalcanal. On 19 August, various units of the 17th Army began to arrive on the island. The threat posed by Allied aircraft prevented the Japanese from using large, slow transport ships to deliver their troops and supplies to the island, so warships were used instead. These ships—mainly light cruisers and destroyers—were usually able to make the round trip down "the Slot" to Guadalcanal and back in a single night, thereby minimizing their exposure to air attacks. Delivering troops in this manner, however, prevented most of the heavy equipment and supplies, such as heavy artillery, vehicles, and much food and ammunition, from being delivered. In addition, they expended destroyers, which were desperately needed for commerce defense. These high-speed runs occurred throughout the campaign and were later called the "Tokyo Express" by the Allies and "Rat Transportation" by the Japanese. With their heavier concentration of surface combat vessels, their well-positioned logistical base at Simpson Harbor, Rabaul, and their victory at the Battle of Savo Island in early August, the Japanese had established operational control over the waters around Guadalcanal at night. However, any Japanese ship remaining within range—about —of American aircraft at Henderson Field, during the daylight hours, was in danger of damaging air