Initially, Allied planners had intended to capture Choiseul Island, at the northern end of New Georgia Sound; the Shortland Islands, off the southern coast of Bougainville; and, the Japanese airbase at Kahili, at the southern end of Bougainville. The fierce Japanese defense of the airfields at Munda Point forced them to reconsider. Leading up to the battle for Vella Lavella, a strategic decision, ultimately successful, had been made to bypass a large concentration of Japanese troops on the island of Kolombangara, between Guadalcanal and Vella Lavella. This caused the Allies to consider and adopt an indirect approach towards Rabaul. It was decided to bypass the Shortland Islands and Kahili, and to seize a lodgment on Bougainville, with the view to establishing an airbase from which to project airpower towards Rabaul. Under this plan Choiseul would not be captured, but would instead be raided as part of a diversion to draw Japanese attention away from Bougainville. The operation to secure a beachhead on Bougainville was codenamed "Cherryblossom" by the Allies.