The Battle of Alligator Creek (aka Battle of the Tenaru) was a formative moment in the American World War Two psyche. After making an unopposed landing on Guadalcanal and taking its mostly-completed airfield at minimal cost, the US Marines had to defend their permitter on the night of August 21st, 1942.
Colonel Kiyonoa Ichiki was sent from the Japanese base at Truk with about 900 tough veteran soldiers to push the Marines off the airfield. These men had originally been slated to assault Midway Island, but the Japanese naval defeat there forced a change in plans. Ichiki was overconfident, and more concerned about retaking the islands of Tulagi, Gavutu, and Tanambogo across the straights, where Japan’s main base in the area had also been captured by Marine Raiders. Marching up the coastline towards Henderson Field, Ichiki’s men hit the thin single strand of Marine barbed wire about about 1:30am on the morning of there 21st. An intense firefight erupted, with the well dug-in Marine positions opening up with .30 caliber and .50 caliber machine guns, small arms, and 37mm canister rounds.
The fighting continued after daybreak, with Ichiki’s men digging in on the east bank of Alligator Creek. The Marines launched a two prong counterattack, with one force crossing the Creek inland and advancing down the east bank while a second group, including several Stuart light tanks, advanced across the sandbar. These two groups linked up in the early afternoon of the 21st, almost completely annihilating the Ichiki Detachment.
This was the first real land combat between American and Japanese forces in which American soldiers were able to report back on their experience. It was here that the US military as an institution learned that the Japanese would die rather than surrender, and this engagement set the American expectations for the rest of the Pacific campaign.
My trip to Guadalcanal was made possible by War Historian Battlefield Expeditions. If you are interested in seeing sights like these in person yourself, check out their upcoming schedule: