Turning Point of the Pacific War: Guadalcanal Island
Japan’s Choices and Consequences After the Midway Defeat
※ This time, it's the 5th part out of a total of 9 parts on the Pacific War.
Japan After Midway
Despite a crushing defeat at Midway, the Japanese military remained undeterred, thinking, “It’s just one loss.” Even after Midway, their strategy of expanding fronts across Southeast Asia and beyond didn’t waver. Their next target was Guadalcanal Island in the Solomon Islands, northeast of Australia.
Strategic Importance of Guadalcanal
Guadalcanal, roughly the size of New Jersey, was a small but critical island for both the U.S. and Japan. If Japan established a base there, the U.S. would lose access to the entire Solomon Islands. The nearest U.S. base was in Hawaii, about 3,728 miles (6,000 KM) northeast. Troops arriving after such a long voyage would be exhausted, making it nearly impossible to challenge a fortified Japanese land base.
<Battle of Guadalcanal, (August 1942–February 1943), Britannica>
The US’s Counterattack Potential
<Battle of Guadalcanal, (August 1942–February 1943), Britannica>
Conversely, if the U.S. seized Guadalcanal, the tide would turn. A base there could launch aircraft to support U.S. ships in the Solomon Islands, giving them a significant advantage. Control of the Solomons would also open a path to Southeast Asia. While Midway was a major blow, the U.S. believed securing the Solomons could tilt the Pacific War decisively in their favor. Neither side could afford to lose Guadalcanal, but Japan acted first.
Japan’s Easy Occupation
Early in the Pacific War, Guadalcanal was nominally British, but its distance from Britain left it undefended. Japan landed without resistance, effectively claiming it. Non-combat units were sent to build an airfield, prioritizing development over defense. Confident after Pearl Harbor, Japan optimistically assumed a U.S. counterattack would take time.
Japan’s Miscalculation
<Japanese Army>
This assumption wasn’t deeply analyzed—just a casual, “After that attack, they won’t come soon.” It proved disastrously wrong. Right after Midway, the U.S. dispatched a fleet to Guadalcanal. Far from slowing down, America sent its elite Marine Corps, hardened by rigorous training.
U.S. Marines’ Landing
The Japanese defenders, mostly non-combatants focused on airfield construction, were unprepared for battle. The outcome was predictable: the U.S. won easily, and Guadalcanal fell into American hands. Japan briefly held this vital foothold only to lose it quickly—a worst-case scenario. The U.S. repurposed Japan’s unfinished airfield and facilities to prepare attacks against them.
In the next 6th part, we will cover the story of the Japanese forces recapturing Guadalcanal Island.