Exercise Talisman Sabre is winding down, bringing to an end two weeks of high tempo US-Australia war games around the continent.

Held on alternate years, Talisman Sabre is the most important bilateral set-piece exercise between the ADF and US forces. Beyond its training value, the exercise serves a 'certification' function for formally validating certain capabilities on both sides of the alliance. Successive iterations of Talisman Sabre have contributed to Australia's coveted status as the most 'interoperable' of America's Pacific-based allies, although in quantitative capacity terms it lags behind Japan and Korea.

What did Talisman Sabre 2015 tell us beyond the headlines of alliance solidarity and action footage opportunities for the news networks?

Even by the 'kitchen sink' standards of a biennial exercise between major allies, Talisman Sabre 2015 broke new ground for scale, complexity and the diversity of participating forces.

All told, this year's exercise involved more than 30,000 personnel, 21 ships, 200 aircraft and three submarines. The major US elements, unsurprisingly accounting for the lion's share of combat power, were the Seventh Fleet's George Washington carrier strike group and the 31st Marine Expeditionary Unit, both  of which are based in Japan. 

The RAAF contribution included weapons training, tanker refueling for the US Navy's F/A-18 Super Hornets, and an E7-A Wedgetail aircraft to test interoperability in battlespace management.

Capping off the aerial segment, a pair of B-52 bombers assigned to US Strategic Command flew a 44-hour round trip from Louisiana to target areas in the Northern Territory, demonstrating the 'ability to project its flexible, long-range global strike capability' and 'to synchronize strategic activities...with a key ally in the US Pacific Command'. 

Large-scale amphibious operations involving seaborne landings and helicopter assaults formed the centerpiece of Talisman Sabre 2015. For the first time, the exercise was divided between training locations in the Northern Territory and central Queensland. The official Facebook page claimed this was the largest amphibious operation in which Australia has participated since World War II.

That being the case, it is important to realise that most of the amphibious assets were American. Given the former Chief of Army's enthusiasm for developing an Australian amphibious concept back in 2013, the ADF contribution at Talisman Sabre was modest. Two hundred and fifty embarked troops from 2nd Battalion Royal Australian Regiment took part in the Fog Bay landing, and HMAS Choules was the sole Australian amphibious ship available for the exercise. 

Plans to use HMAS Canberra, the first of the new amphibious ships, were previewed well in advance. But the LHDs have encountered teething problems and didn't take part. Once they are fully operational, these 27,500-tonne behemoths will provide a step-change in amphibious capability. However, amid the many competing demands in the RAN's modernisation program, it's looking increasingly doubtful whether the ADF will be able to meet its certification target for Australia's amphibious capability at Talisman Sabre 2017.

Special forces units from the US, Australia and New Zealand also took part in a mock night-raid near Darwin. Interoperability between ANZUS special forces has always been among the tightest.

More surprising was the size of New Zealand's overall contingent at Talisman Sabre 2015. Ships and aircraft were deployed, with over 500 personnel committed. This was a significant scaling up of Wellington's military re-commitment to the ANZUS fold, building on New Zealand's earlier participation in Exercise Dawn Blitz, alongside Japanese and US amphibious forces, off the Californian coast in July 2013

Particular attention was paid this year to the small contingent of 40 Japanese troops embedded with the US Marines, geopolitically significant given Japan's ongoing defence 'normalisation' and the recent expansion of Japan-Australia bilateral security cooperation. Japan's Self-Defense Forces are somewhat further down the track of developing a stand-alone amphibious capability than Australia. 

The embedding of Japanese and New Zealand contingents with the US Marines and ADF respectively was the most noteworthy innovation to Talisman Sabre 2015, lending the core bilateral format a loose quadrilateral aspect. It remains to be seen how significant this is as a precursor for wider defence cooperation involving two of Washington's traditionally reticent Pacific allies. But China is likely to have taken note, regardless of whether a strategic signal was intended or not, and despite official assurances that Talisman Sabre is not aimed at third countries. 

Australia, New Zealand and Japan also share a common interest in the stability and humanitarian support of Melanesian countries, for which their nascent amphibious capabilities could be used in concert in the future. Talisman Sabre is not only about 'high-end' war-fighting but practicing interoperability at lower levels of intensity, where amphibious forces are in any case more likely to be survivable.

The interesting decision to split Talisman Sabre 2015 into two geographically separate locations within Australia could have been made simply on practical grounds. But bifurcation of the main exercise components would also be helpful for testing the command and control of concurrent operations in different theatres. Intriguingly, that could point to scenarios for future mid-to-high intensity armed conflict that are more geographically disbursed across the Indo-Pacific than commonly assumed.

Interoperability aside, the unique value of Talisman Sabre to the Americans is the access it gives US forces, the Marines in particular, to the vast training areas only Australia can offer. That said, US willingness to maintain the certification status of Talisman Sabre in future should not be taken for granted.

Photo courtesy of Facebook user Talisman Sabre.