In the aftermath, the US perimeter was slowly expanded and further echelons arrived to unload stores as base development operations began. By late November, an airstrip had been established inside the perimeter. This became fully operational in early December. Throughout the remainder of 1943, the perimeter was expanded further, allowing the establishment of several more airfields. These later played a key role in the neutralization of Rabaul from the air. Throughout 1944 and 1945, follow-on forces from the US Army and then the Australian Army arrived as the Allies conducted operations to secure the rest of the island. This was only partially completed by the time the war came to an end in August 1945.