The ease with which the Japanese accomplished their initial objectives led to the severe underestimation of the enemy and the resultant failure to concentrate the IJN's superior forces at key places and times. As a result, the critical months of May and June 1942 saw the IJN lose both its offensive power and the initiative. The Second Operational Phase was planned to expand Japan's strategic depth by adding eastern New Guinea, New Britain, the Aleutians, Midway, the Fiji Islands, Samoa, and strategic points in the Australian area. However, the Naval General Staff, the Combined Fleet, and the Imperial Army, all had different views on the next sequence of operations. The Naval General Staff advocated an advance to the south to seize parts of Australia, however, the Imperial Japanese Army declined to contribute the forces necessary for such an operation, which quickly led to the abandonment of the concept. The Naval General Staff still wanted to cut the sea links between Australia and the United States by capturing New Caledonia, Fiji, and Samoa. Since this required far fewer troops, on March 13 the Naval General Staff and the Army agreed to operations with the goal of capturing Fiji and Samoa. The Second Operational Phase began well when Lae and Salamaua located on eastern New Guinea were captured on March 8. However, on March 10, American carrier aircraft attacked the invasion forces and inflicted considerable losses. The raid had major operational implications since it forced the Japanese to stop their advance in the South Pacific and this was to be the last of the uninterrupted victories for the Japanese until the Combined Fleet provided the means to protect future operations from American carrier attack.