Joint Warfare in the Near Region: Guadalcanal 1942

“The enemy will certainly not have the kindness to say how strong he is, what are his general designs, or what he is commissioned to do, and in what manner he will strive to attain his end.”

Verdy du Vernois[1]

This piece intends to describe one example of the historical challenge of joint warfare for Australia in its region. That is, where objectives may be characterised by the geographic boundaries of islands, with emphasis on the primacy of sea and air control, as a prelude to success in island-centric warfare.

The 7-month campaign for Guadalcanal offers that neither belligerent intended to fight on that specific island, and the ability to muster support from land-based air and distant naval forces was in question on an almost daily basis. Moreover, the tension between strategy and the limitation of already stretched resources forced both sides to double-down much longer than anticipated for greater cost than initially calculated. This example begs the question: If this is a place the ADF will likely contest in the future, then what lessons will we relearn for those that were paid in blood in 1942?

The late professor Jeffrey Grey posited that the months following the fall of Singapore in February 1942 seemed to carry with them the direct threat of a Japanese invasion of Australia. Air raids continued in the north and west, and Darwin was bombed repeatedly. Since 1939 and with a legacy of neglect during the interwar period, Australia’s forces were incapable of resisting a serious Japanese attempt at lodgement on the Australian mainland due to the following:

1. the air force lacked useful quantities of modern aircraft and the industrial base could not replace that which was lost anyway;
2. the navy was too small to put up any resistance on its own terms and lacked any balance akin to other serious navies at the time; and
3. the army, though large and experienced through service in North Africa and the Mediterranean, could not be moved around or beyond the the country with any speed.

The continuing lack of strategic road and rail networks, especially in the north and west, was another legacy of short-sighted planning in the 1920s and 1930s.[2] Australia’s military forces were too small to offer useful strategic options against Imperial Japan in the near region, and therefore, relied on US power projection. It was a confronting moment for Australia, but it would also signal a turning of the tide for Australia and its Allies in the Second World War’s Pacific Theatre.

Prioritisation by Allied leaders to defeat ‘Germany First’ at the ARCADIA Conference in late 1941 led to a limited offensive to halt Japanese advances along the vital line of communications from the US to Australia and New Zealand by mid-1942. Part of this plan entailed that US infantry divisions would hold the hard shoulders of Fiji and northern New Zealand with a small maritime patrolling presence astride the major sea lanes to Eastern Australia.

This presence was considered to be enough until the US decided to commit the 1st Marine Division on 2 July 1942 on what became a long and bloody struggle for the island of Guadalcanal – a hitherto unnamed objective in the remote Solomon Islands that the world would come to know intimately between 7 August 1942 and 9 February 1943. Codenamed ‘Operation WATCHTOWER’, the US sought to deny the Japanese the ability to sever the allied lines of communication in the South Pacific by seizing advanced bases in the Solomon Islands and the adjacent Bismarck Archipelago, but the operation grew to represent something else entirely.

Japanese overreach met with Allied doggedness, which was further influenced by public perception on the US home front, this sentiment combined to turn an operational-level encounter battle on Guadalcanal into a prolonged series of bloody island-centric engagements. As many as 24, 000 Japanese soldiers were killed to 5, 800 US dead and wounded, and the non-combat deaths from tropical diseases like malaria numbered in the thousands.[3]

Furthermore, the Japanese offensive toward their Southern Resource Zone (SRZ) in late 1941 ultimately failed at Guadalcanal by the end of 1942, as the Japanese Imperial General Headquarters (IGHQ) could not reach agreement on the practical limits of their offensive operations. The institutional split between the Imperial Japanese Army (IJA) and Imperial Japanese Navy (IJN) drove a difference in strategic decision-making, apportioning limited shipping for assault and resupply, and therefore an operational approach to the South Pacific where the IJN agenda outpaced the overall Japanese imperial strategy.

According to Saburo Hayashi: “This was fault was… attributable to the absence, on the part of the Naval High Command, of definitive views concerning the limits of their offensive capabilities. Hence their urgent insistence upon executing operations beyond the national capacity – such as the proposed seizure of Hawaii or Australia.”[4] The strategic lesson to limit military objectives in accord with the strategy is observed by Clausewitz: “The strategist must therefore define an aim for the entire operational side of the war that will be in accordance with its purpose.”[5] In this sense, both sides failed to limit their own objectives.

The Japanese requirement for security of the SRZ became a campaign to interdict Allied lines of communication, which subsequently proposed the possibility of invasion. In his account of amphibious operations in World War II, historian Frank Hough posited: “The Japanese conquest string had ended in the Solomon Islands and New Guinea, and never had a firm knot tied in the end of it.”[6] Consequently, Japanese ends were ultimately usurped by their ways. The enduring tyranny of archipelagic geography, and the interplay between the ocean and littoral, were insurmountable for the IJN who could never reconcile the size of the physical objectives, which was over a multitude of islands, with the size of their available forces.

Despite Imperial Japan’s strategic failings, Allied strategy was as fallible as that of the Japanese in many ways. Public perception drove domestic politics, thereby emphasising the allied response to Japanese counterattacks on Guadalcanal. For this lesson, Clausewitz illustrates the dangers of escalation. “The degree of force that must be used against the enemy depends on the scale of political demands on either side... too small an effort can result not just in failure but in positive harm, each side is driven to outdo the other.”[7] Thus, Guadalcanal symbolised the doggedness of the American people embodied in the struggle with Imperial Japan.

Hough states that - “It was everything the United States could do at that moment against everything the Japanese could manage at that place…. the headlines from Guadalcanal did more for home front morale than did the fast carrier raids of 1942.”[8] Resultantly, the influence of public perception drove the US JCS decision to reinforce Guadalcanal for 5 months longer than the 2-month campaign plan intended. A lesson is that this factor is a modern reality – defining criteria for success should engender prudence in the selection of operational objectives which are, in some way, relatively achievable for the size of the forces available and not wholly dependent on time.

In devising operational objectives that need to be strategically connected and selected with an understanding of the realities of the political situation, the primacy of joint operations in Australia’s region that seek sea and air control is a core lesson. During the series of engagements over Guadalcanal, Japanese air forces repeatedly endeavoured to check the reinforcement of the US Marines then Army on Guadalcanal. Lacking air control, however, the Japanese land forces could accomplish nothing but guerrilla-like actions and the military results were negligible.[9]

In contrast to Imperial Japan’s limited offensives, USMC General Vandegrift was forced to remain on the defensive for the first three months due to persistent air and sea disruption, which meant the lack of reinforcements prevented expansion of Henderson Field, and ensured the force in place was vulnerable to Japanese ground attack.[10] This delayed Vandergrift’s achievement of the initial objective to secure the airfield, prevented his ability to quickly build up combat power to break out, and likely contributed to the battle for Guadalcanal to then becoming characterised as an entire campaign.

Hayashi observed: “In the battles for the island, moreover, the Japanese Army keenly felt the impossibility of gaining victory as long as the command of the air and the sea was not assured.”[11] Securing the needed sea and air control was reflected in the fact that elements of the Japanese garrison on Guadalcanal starved to death during the 7-month campaign due to a lack of supplies, which would have otherwise been delivered if the requisite ships and aircraft were available when or where required.

Operation WATCHTOWER’s increased and undesirable emphasis on the single battle for Guadalcanal was driven by Japanese overreach and the influence of US public perception on a strategy that made both belligerents double-down on a small jungle outpost in the Solomon Islands. The remoteness of Guadalcanal ensured a contest for sea and air control, which would manifest into a series of extremely bloody engagements over a prolonged period that neither side had initially planned for. The inherent inability of both belligerents to assure sea and air control meant that that the battle for Guadalcanal would ultimately prove the beginning of the end for Imperial Japan.

In the future, joint warfare in the near region is a reality for the ADF. We have done it before, our allies have done so, and we will, in all likelihood, have to do it again. Today’s investment in theatre-setting and a persistent approach to developing the institutional processes that enable us to raise and project forces quickly will count. They will also rely on the ability to gain and maintain a modicum of sea and air control beyond our own borders that we are unaccustomed to having the responsibility for.

In considering the future of warfighting in the near region (and despite the acquisition of new and novel technology), attaining realistic air and sea control, the size of the available army to force project for close combat, and the unpreparedness of our forces in the lead up will all matter as it did at the outbreak of war in 1939. With this in mind, Australia should take heed of the lessons of the Guadalcanal campaign to continually invest in an enduring forward presence in the near region with the requisite capacity to do it en masse, and most importantly, at the point of our choosing.