An Island Too Far: Lessons from Guadalcanal for EABO

Under Force Design 2030, the U.S. Marine Corps has been changing its approach to island operations, including establishing the expeditionary advanced base operations (EABO), Marine littoral regiment, and stand-in force concepts.

These developments are important for the Japan Self-Defense Force—especially the Japan Maritime and Ground Self-Defense Forces—as it considers how to work together with the U.S. Navy and Marine Corps to defend the maritime domain. 

EABO is modeled on “Advanced Base Operations in Micronesia,” developed 100 years ago by Marine Major Earl H. “Pete” Ellis. Ellis’s concept for Pacific Island operations was studied before the outbreak of World War II and became the blueprint for the U.S. island-hopping campaign. Because the war between the United States and Japan is the only example of a conflict fought across the Pacific, a vast area dotted with islands, it is important to examine its operations from both perspectives. They are rich with lessons for EABO and other potential operations.

Hangzhou Bay

Although this fact is not well known, the Imperial Japanese Army (IJA) was a pioneer in landing operations. The IJA and the Imperial Japanese Navy (IJN) had studied the 1915 Gallipoli landings and taken lessons from that operation. While the IJN realized it was disadvantageous to engage in gun battles with fortifications, the IJA saw the importance of army-navy cooperation, recognizing that landing operations were a joint effort by land and naval forces.² However, because the IJN’s main potential adversary was the United States, and its focus was on interception at sea in decisive fleet battles, island warfare and landing operations were never explored by the navy as a whole.

Thus, the IJA determined to carry out landing operations on its own—organizing landing forces, developing weaponry, conducting exercises, and completing landing operations unilaterally. To achieve this, it established the IJA Transport Department and built not only small (Syohatsu class) and large (Daihatsu class) landing craft for transporting personnel and artillery, but also the amphibious assault ship Shinshū Maru (8,000 tons) to accommodate and launch these craft. The Shinshū Maru, the first purpose-built landing ship, was equipped with a floodable well deck and two catapults for launching aircraft (although the catapults were removed before she was completed).

The IJA conducted large-scale landing exercises every year from 1916 and achieved a division-sized landing in a joint army-navy exercise in 1929. In 1937, it successfully landed three divisions at Hangzhou Bay during the Second Sino-Japanese War.³

Guadalcanal

The struggle for Guadalcanal was ignited when U.S. Marines seized an airfield established by the IJN to cut off U.S. supply routes to Australia. At the time, though Japan considered the airfield important, it had only a small garrison in place, and the island was easily occupied. The IJN’s main operational policy was to destroy the U.S. Navy fleet at sea, and it had no intention of using the Pacific islands as bridgeheads. 

Some IJN officers did want to use the Pacific islands as bridgeheads, because the Washington Arms Limitation Treaty had put Japan at a disadvantage at sea in terms of battleships. In his New Armament Planning Theory, Rear Admiral Inoue Seibi argued that “fleet decisive battles should not occur, but the island warfare would be more important, and air power should be developed based on the principle of base air power first; light warships and submarines also should be used to deal with island battles.”¹

At the time, however, the IJN possessed only a small land force and could not conduct an island campaign without the IJA, and the IJA was focused on China, the Soviet Union, and Southeast Asia. So no one focused on the island operations that Seibi proposed.

Gap between Hangzhou and Guadalcanal

Japan’s success at Hangzhou Bay was not duplicated in the landing operations on Guadalcanal. The IJA sent large troop formations in three waves to recapture Guadalcanal, but they failed at every turn.

Landing Operations 

First, the IJA and IJN attempted to send in the Ichiki Detachment, consisting of tanks, artillery, and 2,300 riflemen. It took a week following the U.S. landing to organize this unit, and the IJA could get only three transport ships. Furthermore, these ships were slow, so an advance detachment was dispatched by destroyers. The detachment succeeded in landing on Guadalcanal but was defeated by the U.S. Marine Corps with heavy armaments. The IJA had underestimated the size of U.S. troop formations. 

The rest of the Ichiki Detachment moved toward Guadalcanal on the three transports, but all were sunk in the Second Battle of the Solomons, during which the IJN also lost the carrier Ryūjyō. The sinking of the Kinryu Maru, which carried ammunition and food, derailed the transport operation and forced Japan to abort the landing operation. After this, the IJN switched to a safer means of transport (aka Nezumi, or “mouse”) using destroyers, but with limited capacity, the destroyers could not carry heavy tanks and artillery.⁴

The Kawaguchi Detachment, which was deployed after the destruction of the Ichiki Detachment, also faced extreme difficulties in transporting tanks and artillery, but it managed to disembark nearly a brigade of troops and 20 artillery pieces by boats and destroyers along the island. On their landing, however, it became clear that the accurate size of U.S. forces was 10,000 men, including 20 to 30 tanks and several heavy artillery guns. Given the size of the enemy forces, the IJA planned to deploy the 2nd Division, which was stationed on Java, but a shortage of supplies forced the Kawaguchi Detachment to attack alone. The unit could not loiter to await the 2nd Division, and its solo attack failed.

When the 2nd Division was finally deployed, the IJN became more cooperative, partly because it saw the U.S. offensive on Guadalcanal as an opportunity to ambush and destroy the U.S. Navy. It deployed the seaplane tender Nisshin, which could transport and lift heavy artillery. The IJN successfully lifted heavy artillery, but because of the loss of the transports, it could lift only 20 percent of the ammunition and 50 percent of the food it had planned.  

The Japanese force was pleased to get heavy artillery on Guadalcanal, but the 2nd Division’s landing point was too far from the airfield, and the distance to the attack point was all rough roads and jungle. Unable to carry heavy guns alongside, they were forced to prepare for the attack without fire support. Worse yet, the IJA adhered to the traditional tactic of a quiet night attack, only to encounter the enemy’s main force and be defeated.⁵

Faced with the destruction of the 2nd Division, a shortage of local supplies, and a large enemy force, the 17th Army gathered 11 cargo ships and 76 Daihatsu landing craft to transport the 38th Division and obtained 12 escort destroyers from the IJN. But seven cargo ships were sunk before beaching, and the remaining four ships were destroyed by air assault during disembarkation. Ultimately, the 38th Division received only 20 percent of the food and ammunition it initially loaded.⁶

Because of the loss of the cargo ship convoy, only infantry could land, but without ammunition or food. This put Japan at an extreme disadvantage on the front.⁷ The decision to withdraw from Guadalcanal was finally made in December.⁸

Causes of the Failed Attacks

These failures were rooted in a lack of appropriate means of transportation and the failure of continuous logistics.

Transport: The Japanese forces needed fast, large-capacity transports, but because of the lack of time to prepare for operations, they were able to procure only a small number of slow transports. The Shinshū Maru, which had played an important role in the Hangzhou Bay landings as mothership for the Daihatsu landing craft, was not there. She had been hit by a friendly torpedo in March 1942 and was out of service.

Because the transports the IJA could get were slow, the Japanese force could disembark units or supplies only at night, to avoid attack by U.S. aircraft. The IJN attempted to secure a longer disembark time by using destroyers, but the warships did not have enough cargo capacity. Worse, using them for transport limited the amount of ammunition they could carry for their own use. So, the IJN’s disembark window was only four hours per day—even less when moonlight was scarce.⁹ The IJN lost 16 destroyers during the two months of the destroyer transportation campaign, which was more than the planned ship build for the following two years.¹⁰   

Before the war began, the IJA had calculated the number of ships required for transportation, determining 15,000 tons (~2 large ships) would be required to transport one regiment, and 150,000 tons (~10 large ships) to transport one division.¹¹ Based on this, at least 16 vessels would have been needed to transport the Guadalcanal landing forces. (During the Java campaign in 1942, as many as 32 ships were used to transport one division.¹²) This was more than the number of ships allocated to the IJA. In fact, to transport the 17th Army to Guadalcanal, 150 destroyers per month would have been required to meet the IJA’s demand (17,500 personnel, 176 guns, and 500,000 rations, plus ammunition), which was more than the 60 ships the IJN had at the time.

In addition, IJN escort fighters from Rabaul could stay over Guadalcanal for just 15 minutes because of their limited combat range, which also contributed to the loss of the transports.¹³

After the 38th Division failed to land on Guadalcanal, Tokyo determined 620,000 tons of additional transport ships would be needed, but this was not feasible.¹⁴

Logistics: The inability to replenish supplies made it impossible to continue operations, and the longer enemy resistance continued, the worse the situation became. The most dangerous threat for the IJA was not enemy attack but starvation and disease. Of the 20,000 Japanese casualties in the Guadalcanal campaign, only a few thousand were killed in battle, while 15,000 died of malnutrition and malaria. 

The Japanese forces attempted to supply the front line by all means, including dropping drums from destroyers at night, but few made it ashore, and what did arrive had to be transported to the front line by manpower over a two-day walk.¹⁵ Considering that only 20 percent of the supplies planned for Guadalcanal were actually delivered, the Japanese forces needed five times the supplies and transport ships from the beginning. 

Lessons for Today

Comparing the success of the Hangzhou Bay landings with the failure of the Guadalcanal landings, it becomes clear that transportation and continuous logistics are indispensable for landing operations in enemy territory. Japanese forces needed more transport ships and Daihatsu-class tender ships such as the Shinshū Maru.   

The IJA was a pioneer not only in landing operations, but also in the development of assault landing craft (the Daihatsu class) and their tender ship (the Shinshū Maru). But few initially recognized the importance of these assets. Only when Japanese forces faced defeat on Guadalcanal did they realize more Daihatsu motherships were needed, but it was too late.

The importance of the landing craft carrier has not diminished. Today, when the U.S. Marine Corps intends to deploy Marine littoral regiments with air defense and antiship missile batteries or stand-in forces as part of EABO, transportation is essential. Construction and acquisition of the Landing Ship Medium in significant numbers will be key.

In addition, when a new base of operations is acquired, it must be not only defended, but also supplied. Once the Marine littoral regiment and stand-in forces come ashore, their activities will be restricted unless they are constantly supplied, and given that 75 percent of Japanese losses on Guadalcanal were the result of disease or starvation, continuous supply to the landing sites could be a life-or-death challenge. The longer the supply line, the more difficult it is to protect it from enemy attacks, and the fewer supplies reach the front line. As maritime forces grow more distributed, stronger supply lines will be needed.  

“Advanced Base Operations in Micronesia,” the model for Force Design 2030, was scrupulously studied before World War II. So, too, should we today review both Japanese and U.S. island operations during the war. The Japan Self-Defense Force and U.S. military should examine the war in the Pacific to find lessons for each other.