Battle of Savo Island - Aftermath

Aftermath

At 04:00 on August 9 Patterson came alongside Canberra to assist the cruiser in fighting her fires. By 05:00, it appeared that the fires were almost under control, but Turner, who at this time intended to withdraw all Allied ships by 06:30, ordered the ship to be scuttled if it was not able to accompany the fleet. After the survivors were removed, the destroyers USS Selfridge and USS Ellet sank Canberra with torpedoes and gunfire.

Later in the morning of August 9 General Vandegrift advised Admiral Turner that he needed more supplies unloaded from the transports before they withdrew. Therefore, Turner postponed the withdrawal of his ships until mid-afternoon. In the meantime, Astoria’s crew tried to save their sinking ship. Astoria’s fires, however, eventually became completely out of control, and the ship sank at 12:15.

On the morning of August 9, an Australian coastwatcher on Bougainville radioed a warning of a Japanese airstrike on the way from Rabaul. The Allied transport crews ceased unloading for a time but were puzzled when the airstrike did not materialize. Allied forces did not discover until after the war was over that this Japanese airstrike instead concentrated on Jarvis south of Guadalcanal, sinking her with all hands. The Allied transports and warships all departed the Guadalcanal area by nightfall on August 9.

In the late evening of August 9, Mikawa on Chōkai released the four cruisers of Cruiser Division 6 to return to their home base at Kavieng. At 08:10 on August 10, Kako was torpedoed and sunk by the submarine USS S-44 110 kilometers (70 mi) from its destination. The other three Japanese cruisers picked up all but 71 of her crew and went on to Kavieng.

From the time of the battle until several months later, almost all Allied supplies and reinforcements sent to Guadalcanal came by transports in small convoys, mainly during daylight hours, while Allied aircraft from the New Hebrides and Henderson Field and any available aircraft carriers flew covering missions. During this time, Allied forces on Guadalcanal received barely enough ammunition and provisions to withstand the several Japanese drives to retake the islands.

Despite their defeat in this battle, the Allies eventually won the battle for Guadalcanal, an important step in the eventual defeat of Japan. In hindsight, if Mikawa had elected to risk his ships to go after the Allied transports on the morning of August 9, he could have ended the Guadalcanal campaign at its inception, and the course of the war in the southern Pacific could have gone much differently. Although the Allied warships at Guadalcanal that night were completely routed, they did accomplish their mission, which was to protect the vital transports from harm. Many of these same transports were used many times to bring crucial supplies and reinforcements to Allied forces on Guadalcanal over succeeding months. Mikawa's decision not to destroy the Allied transport ships when he had the opportunity would prove to be a crucial strategic mistake for the Japanese.

A formal United States Navy board of inquiry, known as the Hepburn Investigation, subsequently prepared a report of the battle. The board interviewed most of the major Allied officers involved over several months, beginning in December 1942. The report recommended official censure for only one officer: Captain Howard D. Bode. The report stopped short of recommending formal action against other Allied officers, including Admirals Fletcher, Turner, McCain, and Crutchley, and Captain Riefkohl. The careers of Turner, Crutchley, and McCain do not appear to have been affected by the defeat or the mistakes they made in contributing to it. Riefkohl, however, never commanded ships again. Captain Bode, upon learning that the report was going to be especially critical of his actions, shot himself in his quarters at Balboa, Panama Canal Zone, on April 19, 1943, and died the next day. Crutchley was gazetted with the Legion of Merit (Chief Commander) in September 1944. Admiral Yamamoto signaled a congratulatory note to Mikawa on his victory, stating, "Appreciate the courageous and hard fighting of every man of your organisation. I expect you to expand your exploits and you will make every effort to support the land forces of the Imperial army which are now engaged in a desperate struggle." Later on, though, when it became apparent that Mikawa had missed an opportunity to destroy the Allied transports, he was intensely criticised by his comrades. Admiral Turner later assessed why his forces were so soundly defeated in the battle:

"The Navy was still obsessed with a strong feeling of technical and mental superiority over the enemy. In spite of ample evidence as to enemy capabilities, most of our officers and men despised the enemy and felt themselves sure victors in all encounters under any circumstances. The net result of all this was a fatal lethargy of mind which induced a confidence without readiness, and a routine acceptance of outworn peacetime standards of conduct. I believe that this psychological factor, as a cause of our defeat, was even more important than the element of surprise".

Historian Richard B. Frank adds that, "This lethargy of mind would not be completely shaken off without some more hard blows to (U.S.) Navy pride around Guadalcanal, but after Savo, the United States picked itself up off the deck and prepared for the most savage combat in its history."