In early 1943, Takao supported evacuation of Guadalcanal. The force consisted of the carriers Zuikaku, Zuiho- and Jun’yo-, the battleships Kongo- and Haruna, heavy cruisers Atago, Takao, Myoko and Haguro, the light cruisers Nagara and Agano, and 11 destroyers. The Japanese transports were successful in evacuating 11,700 troops from the island.
Under the command of Inoguchi Toshihira, Takao operated in the central Pacific from her base at Truk. She returned to Yokosuka Naval Arsenal on 26 July for the installation of additional anti-aircraft guns. After returning to Truk on 23 August, she continued on to Rabaul on 27 August, disembarking army troops and supplies.
In response to American carrier aircraft raiding in the Gilbert Islands, Takao sortied with Vice Admiral Jisaburo- Ozawa’s fleet to engage the American carriers. The fleet consisted of the aircraft carriers Sho-kaku, Zuikaku and Zuiho-, the battleships Yamato and Nagato, heavy cruisers Myo-ko-, Haguro, Tone, Chikuma, Mogami, Atago, Takao, Cho-kai and Maya, the light cruiser Agano and fifteen destroyers. Despite extensive searches, this force failed to make contact with the American striking force and returned to Truk.
On 5 November 1943, she was refueling at Rabaul when she came under attack by SBD Dauntless dive bombers from USS Saratoga (see Attack on Rabaul). Takao was hit by two bombs, killing 23 crewmen and damaging her steering; she was forced to return to Yokosuka for dry dock repairs. During the repair work, additional anti-aircraft guns were fitted, as was a Type 21 radar. Repairs were not complete until 18 January 1944.
Japanese struggles in New Guinea and in what was left to them of the Solomon Islands had continued and intensified throughout the autumn, but a new and worrying development for the leadership in Tokyo were the new initiatives that the Americans had been taking in other parts of the ocean. If their action in the Aleutians had been about restoring pride, what did the Japanese make of the American landings on two of the Ellice Islands (Nukufetau and Nanomea) and on Baker Island in the Gilbert Islands at the end of August, or of the intensive bombing raids carried out against Marcus Island, Tarawa and Wake Island in the following weeks? As none of these actions were necessary for the success of future operations against Bougainville or New Britain, the notion that the Americans may have been devoted to a single overarching strategic plan for the Pacific went out of the window. What these raids had done was to show that the Americans were prepared to mount simultaneous operations across thousands of miles of ocean if they deemed the risks to be worth it. Rueful Japanese military officers could consider that their enemy had learnt a thing or two from studying the moves Yamamoto had made so brilliantly in the early months of the war. Confirmation – if such was needed – of the separate strands of American policy was provided in November with the opening of the invasion of Bougainville in the Solomons and the costly attacks on the islands and atolls of the Gilbert Islands.
Recovering Bougainville from the Japanese was always expected to be a tough assignment for the Americans. Apart from being the largest of the Solomon Islands, it had the most enemy soldiers (roughly 40,000) defending it and was near enough to the regional base of Rabaul in New Britain (approximately 200nm or 370km) to receive regular reinforcements of both troops and supplies, as well as substantial air cover should it be attacked or invaded. For this reason, the USAAF had begun a massive air offensive against Rabaul on 12 October in a bid to try to lessen its influence, wreck its infrastructure and destroy as many planes both on the ground and in the air as possible ahead of an invasion. These massed attacks drew forth a swift Japanese response from Admiral Mineichi Koga, Yamamoto’s successor as C-in-C. In a novel twist he decided to transfer the aircraft from six of his carriers (Hiyo, Junyo, Ryuho, Shokaku, Zuiho and Zuikaku) to the air base at Rabaul (Operation RO) in order to supplement the numbers of Japanese planes on New Britain capable of countering the American offensive. It would prove to be a costly error. So many of these planes were lost in the American carrier raids on Rabaul and in the skies over New Britain and Bougainville that Koga was forced to withdraw them and fly them back to Truk (Chuuk) on 12 November.
After failing with two diversionary exercises in the Treasury Archipelago and on the island of Choiseul to delude the Japanese into thinking that Bougainville would not be their next target, the Allies began their invasion proper with the landing of 14,321 Marines and their supplies from a convoy of twelve transports at Cape Torokina in the early hours of 1 November. Escorted by eleven destroyers, four destroyer minesweepers and eight minesweepers, the invasion fleet got ashore on Bougainville without any interference. It wouldn’t remain like that for long. While the Americans were still engaged in building up a substantial beachhead at Empress Augusta Bay (known to the Japanese as Gazelle Bay), Admiral Tomoshige Samejima, in command of the 8th Fleet, decided to send the ships he had immediately available at Rabaul to attack the invasion fleet. As a result, the two heavy cruisers Haguro and Myoko, accompanied by the light cruisers Agano and Sendai and six destroyers, reached the Empress Augusta Bay during the night of 1-2 November and found the four cruisers and eight destroyers belonging to the American task force TF 39 waiting for them. In a confusing encounter in which collisions featured prominently on both sides and most ships received some damage from shellfire, torpedoes or close encounters with their own kind, the Americans had rather the better of the exchanges, sinking both the Sendai and one of the Japanese destroyers and lightly damaging all three of their remaining cruisers. In contrast, only four American destroyers had been hit and of those only one was sufficiently damaged to be put under tow.
Koga felt obliged to make up for the loss and damage from this first incident by sending Vice-Admiral Kurita from Truk to Rabaul on 3 November with a mix of ten cruisers and twelve destroyers. It would again prove to be a costly deployment. Learning from a reconnaissance flight that this fleet had been spotted making its way to Rabaul on 4 November, Rear-Admiral Frederick Sherman, in command of TF 38, prepared a carrier force of forty-five dive and torpedo-bombers and fifty-two fighter planes to attack them. In the wave of attacks that followed their arrival off Rabaul, the Japanese suffered grievous damage to four of their heavy cruisers (Atago, Maya, Mogami and Takao), two of their light cruisers (Agano and Noshiro) and a destroyer in return for downing ten of these carrier aircraft. Viewed from Koga’s perspective this was a very poor return, but more damage to his cruisers followed another raid on the port of Rabaul by twenty-seven land-based Liberator bombers shortly afterwards. Needing no further proof that Rabaul was not what it once was, he duly recalled Kurita’s cruiser squadrons and most of his destroyers to the safety of Truk. This left Samejima again under pressure for he had to try to establish a supply route for the Japanese troops on Bougainville at a time when Allied aircraft were pounding Rabaul more often than not. Unable to prevent substantial reinforcements being landed off Cape Torokina, Samejima soon found himself confronting a new danger in the guise of Rear-Admiral Alfred Montgomery’s Allied task group (TG 50.3) whose three new fast carriers and nine destroyers soon began to take a toll on the 8th Fleet. Truth is often a casualty of war and wishful thinking can just as frequently be used by warriors to turn hope into `fact’. So it was with the returning Japanese pilots who after engaging in a savage series of battles with US naval and air forces off Bougainville recorded vastly exaggerated claims of destruction in which ten carriers, five battleships, nineteen cruisers, seven destroyers and nine transports had been allegedly put to the sword and twenty-four other vessels had been mythically damaged. In reality, the losers had been the Japanese carrier planes which had suffered a horrendous beating with 121 of the total number of 173 being destroyed (70%). Koga’s carrier fleet was for a time something of a misnomer since it didn’t have enough aircraft to function as one. Bougainville would remain a drain on Samejima’s surface fleet for months to come, but it was seen by the military authorities in Tokyo as an acceptable cost as long as the Japanese forces on the island held up the progress of the Americans in the region.