[Insight & Opinion] Japan’s Division Strategy for the Korean Peninsula and Incomplete Liberation

Seventy-seven years ago, we were liberated from Japanese colonial rule. After liberation, Japan withdrew from the Korean Peninsula, but another turmoil began. Was it truly complete liberation?

Yukiko Koshiro (小代有希子), a professor at Nihon University (日本大?), researched Japan’s end-of-war strategy. Her findings are presented in Imperial Eclipse: Japan’s Strategic Thinking about Continental Asia before August 1945. It can be called Japan’s end-of-war geopolitics. The fate of the Korean Peninsula was deeply connected to this.

At that time, Japan analyzed the international situation and recognized cracks forming in the US-Soviet relationship, seeing an opportunity for postwar Japan to revive. To achieve this, Japan judged that it needed to end the war at a point when the Soviet Union entered East Asia, preventing a unilateral US victory.

Japan’s surrender strategy was to create a competitive dynamic between the US and the Soviet Union in East Asia. Vice Admiral Sokichi Takagi (高木?吉), who was in charge of formulating the end-of-war strategy, stated in a midterm report in March 1945 that Japan’s role would only be recognized by the US when the US could not handle the Soviet Union opposing its sole dominance in Asia alone. This was the only path for Japan to regain its status in Asia with US support. Colonel Sakao Tanemura (種村佐孝), head of the War Guidance Section of the General Staff responsible for Soviet-Japanese end-of-war operations, also argued that Japan should surrender after the Soviet Union launched attacks on Manchuria and the Korean Peninsula.

The Japanese command, the Imperial General Headquarters, was already convinced by May 1945 that the Soviet Union would soon enter the war and advance not only into Manchuria but also the Korean Peninsula. Japan’s strategy was to facilitate Soviet entry into the Korean Peninsula while blocking US entry. Essentially, Japan provided the Soviet Union with the opportunity to enter the Korean Peninsula, ultimately inducing the US and the Soviet Union to divide and occupy the peninsula. In early 1945, Japan adjusted its troop deployment on the Korean Peninsula to focus on defending the southern part from the US.

The Japanese army ordered that if the Soviet forces advanced one ri (approximately 0.4 km), they should retreat two ri. The Soviet Union declared war on August 8, 1945, and landed in Unggi, North Hamgyong Province on August 9 without resistance, advancing to Chongjin by August 13. The Soviets were in a position to occupy the entire Korean Peninsula alone. Alarmed, the US created a plan to divide the Korean Peninsula along the 38th parallel for US and Soviet occupation. On August 13, President Truman approved this plan, and the next day Stalin agreed to the US proposal, resulting in the division of the Korean Peninsula. This was the outcome of Japan’s groundwork and the geopolitical compromise between the Soviet Union and the US.

Japan surrendered only after the Soviet invasion began. Fumimaro Konoe (近衛文?), a former prime minister, said that the Soviet entry was a gift from God, allowing the war to end. Although the atomic bombs were dropped due to Japan’s delayed surrender, a geopolitical structure emerged that prevented the US from having sole dominance. This created an environment where the US could not harshly control defeated Japan. Japan cleverly exploited the US-Soviet power struggle to receive full support from the US. The Korean War, which broke out on the divided Korean Peninsula, also greatly contributed to Japan’s economic recovery.

Japan lost the war but created a tense balance of power between the US and the Soviet Union in East Asia, establishing a foothold for survival. As a result, the Korean Peninsula experienced incomplete liberation. It is the Korean Peninsula’s responsibility to create a power balance favorable to itself for true liberation. This is why geopolitical imagination is necessary.

Kim Dong-gi, author of The Power of Geopolitics

This content was produced with the assistance of AI translation services.