The carefully staged AUKUS plan to provide Australia with nuclear-powered submarines (SSNs) will build increased deterrence as each phase is completed, says former Royal Australian Navy chief Tim Barrett.

‘I think the way it’s been described and phased will offer the nation a level of deterrence that builds with each successive phase,’ Barrett tells The Strategist.

Barrett was chief of the RAN from 2011 to 2014. He provides advice to a number of industry organisations and boards.

Barrett says that during his time as navy chief, it was clear that nuclear power was not an option for Australia’s submarines. Over a relatively short time, there had been a significant shift in Australia’s political environment and in allies’ acceptance of the technical exchange that would enable Australia to go down that path. ‘I was a little surprised,’ he says, ‘to wake up with everyone else on 15 September 2021 to hear that at 6.59 am we were a non-nuclear nation, and at 7.01 am, we were a nuclear nation.’

So, what’s changed?

Barrett says the US and UK decisions to share this technology are based in part on deteriorating strategic circumstances. ‘It’s not just about considering the platform. It’s the need to manage the threat, which is a growing number of submarines that will operate in our region, and the need to satisfy yourself that you have an ability to react to underwater warfare, should it be required. It’s a big task, and often it’s beyond the capacity of one nation to be able to achieve it.’

Allies can operate together and share information to ensure integrity of surveillance, he says. ‘It’s a bit like an underwater air traffic control system. You need to know where everyone is so that when you need to act, you can act appropriately and with the speed that’s necessary. The ability to locate and track, and be available to destroy if needed, is a constant and difficult task to achieve.

‘The task of conducting anti-submarine warfare is huge and it’s not just about submarines, either. It’s about surface ships, aircraft, space-based sensors, seabed arrays, and crewed and uncrewed vessels. It doesn’t surprise me that any nation, even with the capacity of the US, looks at its ability to sustain that level of engagement. They will be constantly looking at their own abilities and the abilities of others to support that task.’

Barrett says another factor is Australia’s proven ability to build conventionally powered submarines on a greenfield site and operate them successful for decades. The Collins class submarines have ‘improved measurably our contribution to theatre anti-submarine warfare in this region,’ he says.

‘It’s a very capable submarine. And I think the US has probably realised that we are a capable submarine operator.

‘And we have a submarine force that can exploit it to a full extent. We’re not just the owner of submarines; we’re a user of the submarine force. And I think that’s a big distinction among navies. Can we use them effectively? We use them very effectively.’

Years of close collaboration with the US has convinced it that Australia is a suitable partner to complete this broad-scale, very difficult task, he says.

Following a plan assembled over 18 months by a navy-led but multi-disciplinary taskforce, the program is carefully stepped to build up a potentially lethal deterrent in the region and to get formidable attack submarines into the hands of Australian sailors as quickly as possible.

The US will immediately increase the number of submarine visits to Australian ports and the UK will make regular visits from 2026. While that will establish an SSN presence, it will also provide increasing opportunities for Australia to begin building the industrial capability to service and maintain the boats during their visits.

That will involve the US and UK rotating submarines through the HMAS Stirling naval base in Western Australia by 2027 under a formal process to be designated Submarine Rotational Force—West.

The base will be expanded to support the scale of infrastructure required for nuclear-powered submarines—both visitors and those that will belong to Australia. The UK is expected to provide one of its Astute-class SSNs for these rotations and the US up to four Virginia-class boats.

Apart from bringing strategic weight, that will also increase opportunities for Australian personnel to serve aboard the submarines of both allies to, in the words of US president Joe Biden, help ‘jump-start’ Australia’s capability.

Pending congressional approval, the US has committed to selling three of its Virginia-class ‘hunter-killer’ submarines to Australia in the next decade and it will provide up to five if required.

Australia and the UK intend to start building the submarines in their domestic shipyards before the end of this decade. The UK plans to deliver its first boats to the Royal Navy in the late 2030s. Australian boats will be built in Adelaide and the goal is to deliver the first locally built SSN to the Royal Australian Navy in the early 2040s.

Barrett says that confronted by modern surveillance systems, in the ocean, on the seabed, in the air and out in space, a submarine commander’s task has become steadily more difficult. It is much harder for a conventionally powered submarine to complete its mission because that requires it to come up near the surface to recharge its batteries by using a snorkel mast to run its diesel engines.

‘You may need to react when something occurs, and the nuclear submarine’s ability to put on speed instantaneously and sustain it for as long as needed is a clear advantage,’ he says.

Is the SSN AUKUS plan achievable?

Barrett says that when he was navy chief, he’d anticipated that the plan to replace many of the RAN’s surface ships would generate a cohesive naval shipbuilding national endeavour that would harness a significant level of interest, engagement and resource base across government and industry.

‘Such an endeavour requires new thinking, commitment and a constant level of governance while trying to avoid a reversion to past practice and a business-as-usual approach. Clearly, when you have nuclear stewardship as the core, the bar is raised enormously and all of these facets must be demonstrated to those who are about to release the technical detail to you. You need to demonstrate that you understand the issues, you have the resources to resolve the myriad problems that will arise out of AUKUS.’

Barrett says he’s heartened by the extent of the work that’s gone into ensuring that the project will be delivered safely, appropriately and effectively.

‘There’s a committed, deliberate and disciplined approach to how we’ll eventually be able to do more of this ourselves, so I think the plan can work. I accept that it’s going to take a long time, but it’s not a binary choice that says we don’t have this capability until we have everything.’