On the night of 1 November 1943, American forces landed at Cape Torokina on Bougainville, the southern flank of the Allied advance toward Rabaul. The screen of cruisers and destroyers at Empress Augusta Bay turned back a Japanese counterattack that night, but Admiral Mineichi Koga, commanding the Combined Fleet at Truk 800 miles to the north, responded fast. Rabaul-based aircraft struck the landing site the next morning. Dive bombers tracked the American surface fleet and put three bombs into a cruiser despite the AirSols fighters flying overhead. And over the next few days, Koga sent a heavy cruiser force down from Truk to reinforce Rabaul - the kind of surface strength that could cut the Bougainville landing off from its supply line. Halsey's own battleships and most of his cruisers were gone, transferred north to cover the upcoming invasion of Tarawa. All he had in hand was two aircraft carriers.

Rear Admiral Frederick C. Sherman commanded Task Force 38. Halsey ordered him north through the night of 4-5 November to get within launch range of Rabaul for a daybreak strike. Sherman approached behind a weather front for concealment. At dawn on 5 November, he launched all 97 of his available aircraft - every plane he had - leaving nothing behind as combat air patrol over his own carriers. Fighters from the newly captured airfield at Vella Lavella and from Barakoma flew out to meet the carrier force and provide what protection they could. The orders to the aircrews were deliberately modest: damage as many warships as you can. Do not try for sinkings. The point was not to win a naval battle - it was to break up the cruiser force before it could sail against Bougainville.

The Navy strike hit Simpson Harbour at daybreak on 5 November. An hour later, 27 B-24 Liberators of the Fifth Air Force, escorted by 58 P-38s, came in behind them. The heavy cruiser Maya took a bomb above one of her engine rooms that killed 70 of her crew. Mogami was hit by a 500-pound bomb that set her afire and killed 19. Takao took two 500-pound bombs and lost 23 men. Atago was slightly damaged by near-misses; Chikuma lost one crewman to a hit near an anti-aircraft gun. Three destroyers took light damage. The attack was short, violent, and complete enough. Under the threat of more strikes, most of the surviving Japanese warships departed for Truk the next day. Koga's cruiser force, the thing that had forced Halsey to throw his carriers into a target Navy doctrine said could not be attacked, was no longer a factor in the Bougainville campaign. American aircraft losses were light.

Two days later, Rear Admiral Alfred E. Montgomery's Task Group 50.3 arrived - the carriers Essex, Bunker Hill, and the light carrier Independence, among the first of the new fast carriers that would dominate the late-war Pacific. On 11 November, Halsey used Montgomery's task group alongside Sherman's to hit Rabaul again. Sherman launched from near Green Island northwest of Bougainville in bad weather, struck at around 08:30, and retired south undetected. Montgomery launched from the Solomon Sea 160 miles southeast of Rabaul. The light cruiser Agano, which had stayed behind after the 5 November raid, was torpedoed and heavily damaged. A destroyer took a direct bomb hit while loading torpedoes near the harbor mouth, blew up, and sank with 148 of her crew. The Japanese counterattacked with 120 aircraft against the American carriers that afternoon. Thirty-five of those planes did not return. The American ships were not damaged.

The two strikes changed the equation in the South West Pacific. Rabaul had been the anchor of Japanese naval power in the region since its capture from the Australians in January 1942 - called "the Pearl Harbor of the South Pacific" by the men who manned it. After November 1943, it was still a fortress, but a hollow one. The cruiser force that had made it a threat to amphibious operations had been pulled back to Truk. With Bougainville and Buka in Allied hands, land-based US Navy and Marine Corps bombers could reach Rabaul from the south for the first time, and on 17 December 1943 the systematic air campaign to isolate the base began. By the end of the war, tens of thousands of Japanese troops were still dug into Rabaul's tunnels and gun positions, fighting a war that had long since moved on without them. The Allies did not capture Rabaul. They simply flew past it, as Halsey had bet they could, once the cruisers were gone.