Kula Gulf
The Japanese had won a tactical victory, and had demonstrated that they possessed superior night-fighting techniques, but of the action the naval historian Samuel Eliot Morison wrote: "A string of such victories add[ed] up to defeat." Paul Dull further describes the battle as one in a "series of Pyrrhic victories for the Japanese" as they were unable to match the capacity of US industry to replace their losses. Ainsworth's force was unable to prevent the flow of Japanese reinforcements south as the lines between Bairoko and the Diamond Narrows remained open. Nevertheless, strategically, the battle forced a change in Japanese tactics. Combined with the earlier Battle of Kula Gulf, the engagement eventually deterred the Japanese from future use of the Kula Gulf to reinforce Munda. The Allied naval commander, Admiral Chester Nimitz, also changed tactics, deciding that the use of cruisers in the confined waters around the Solomon Islands was too dangerous and ineffective. Meanwhile, for the Japanese destroyer losses necessitated the use of "Daihatsu" barges to move reinforcements between the Shortland Islands and the Kula Gulf. Consequently, the U.S. Navy concentrated responsibility for its interdiction efforts on its destroyer force and PT boats.