Operation A

Japanese strategy

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July 22, 2026

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Operation A was a Japanese defense plan developed in response to the realization that Japan was on the defensive after the fall of Guadalcanal. The strategy involved strengthening existing defensive positions while launching counterattacks. Priority was given to defending New Guinea and the Solomon Islands. This plan was later revised to establish a final defensive line from West New Guinea and the Carolines to the Marianas by spring 1944, to be held at all costs as a base for counterattacks. The operation was further refined with land-based air forces and a naval force of carriers. However, the attrition of Japanese forces continued, and the plan faced setbacks with the deaths of key admirals.1

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World War II
The central Pacific
…a new defense plan, “Operation A,” relying on their remaining 1,055 land-based aircraft in the Marianas, in the Carolines, and in western New Guinea and on timely and decisive intervention by a sea force, which should include nine aircraft carriers with 450 aircraft. But in the spring of 1944…
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…a new defense plan, “Operation A,” relying on their remaining 1,055 land-based aircraft in the Marianas, in the Carolines, and in western New Guinea and on timely and decisive intervention by a sea force, which should include nine aircraft carriers with 450 aircraft. But in the spring of 1944…
Read More