To most Australians, the campaign conducted against the Japanese in New Guinea during World War II is typified as a jungle ‘Army’ fight across the Kokoda Track. Very few think this to have been a maritime campaign. Nowadays, new and emerging concepts provide new definitions on what the 39th Australian Infantry Battalion (39th Bn) conducted and victoriously achieved.

In accordance with the new United States Marine Corps (USMC) doctrine, Australian operations in New Guinea could be classified as an Expeditionary Advance Base Operation (EABO) and littoral warfare manoeuvre. It is easy to foresee the first critics to this statement: there was no projection of land power from the sea in the traditional sense, so it cannot be classified as ‘littoral’.

This is partially incorrect, because 39th Bn was inserted into Port Moresby by a ship, the RMS Aquitania, and the unit rapidly adapted to the changing situation in order to provide the desired effect in support of the Australian and Allied (maritime) campaign in the South-East Pacific.

EABO

In accordance with its ‘Tentative Manual for Expeditionary Advanced Base Operations,’ 2nd Edition (May 2023), the USMC defines EABO as a form of expeditionary warfare that involves the employment of mobile, low-signature, persistent, and relatively easy to maintain and sustain naval expeditionary forces from a series of austere, temporary locations ashore or inshore within a contested or potentially contested maritime area in order to conduct sea denial, support sea control, or enable fleet sustainment.

The first part of this definition comes close to the 39th Bn operations in New Guinea; the last part too, if we consider that, in the end, it was a combination of what this unit achieved on denying key terrain, the maritime interdiction campaign against Japanese supply lines and the amphibious movements to outflank their defensive positions that forced the Japanese forces back from New Guinea to their final defeat.

The five characteristics of USMC EABO are stand-in forces – mobility, persistence, low signature, cost-effective and integrated naval forces – confirm that the Australian forward-deployed unit could be tagged as an EABO example. Indeed, the 39th Bn, as a stand-in force, was able to be inserted below the threshold of violence, engaging with allies and partners within the potential adversary’s Weapons Engagement Zone (WEZ), and finally conduct the kinetic engagement of enemy forces, forcing them to expose themselves to the rest of the friendly combined force.

In terms of mobility, we all know the difficulties which were faced by the Australian forces to fight, move, and sustain along the Kokoda Trail and in the New Guinea jungle. This was only possible thanks to the infantry skills and resilience of the soldiers, and the support of the Papuan Infantry Battalion troops, who served fighting or sustaining the unit.

In regard to the persistence, 39th Bn made an extraordinary job on sustaining themselves in an austere setting, protecting themselves through effective detection and targeting, all keeping a light posture dictated by the terrain and mission. Maintaining a low signature allowed 39th Bn to remain positioned to achieve the desired operational effects while conducting localised movement and manoeuvre.

Finally, for 39th Bn, the integration with the naval forces was at the highest level: General MacArthur issued a specific order to Major General Morris to send out forces to first secure Kokoda, and its airfield, and then possibly proceed to Buna, to be joined by combined and joint forces by sea to use the latter as a raid launching position on Japanese positions.

Littoral Warfare

Using the current military vocabulary, 39 AIB operations sought to deny at the Japanese establishment of an Anti-Access Area Denial (A2AD) bubble in New Guinea. 39th Bn's achievements in Kokoda, therefore, could be also considered a form of archipelagic or littoral manoeuvre in accordance with the Australian Army Research Centre (AARC) which defines littoral manoeuvre as 'the use of the littoral to achieve control of the maritime domain from the land, as well as projecting and sustaining the force ashore'.

As underlined by Commander 1st (Australian) Division, Major General Scott Winter, the core of littoral warfare is sustainment: “It is get there and sustain it.” 39th Bn's operations in New Guinea highlighted the challenges in sustaining an EABO and a littoral force, specifically long and arduous land and sea lines of communication (LOC), with stores moved by rail to Brisbane, by ship to Port Moresby, and air dropped or hauled over the Kokoda Trail by Australian soldiers and Papuan carriers working their way over steep mountains, razorback ridges, and dense jungles.

Transposing 39th Bn action to contemporary operations, it could have land-based long range fires attached to allow the unit to play a greater vital role within the Integrated Force by contributing to a multi-domain denial and control the Vitiaz Strait and the Solomon Sea.

Conclusion

Noting the considerations discussed above, the answer to the original question can be considered a ‘yes.’ In any case, despite the positive or negative answer, it is clear that any effect into the littoral battlespace, in geographical sense, will be oriented to the sea in the future. Military forces will work in littoral operational areas that are compressed in size, in the WEZ, with a significant number of units working to achieve a level of superiority (local or extended) in all domains.

As successfully showed by the Ukrainian forces in the Black Sea, it is clear that these units need to possess the capability to operate decentralised, but in coordination, to provide the most efficient offensive/defensive effects and overcome any enemy efforts in the same littoral.