There’s a saying about submarine warfare: ‘there are two types of naval vessels – submarines and targets.’ Nuclear-powered submarines, SSNs, are the true apex predator of the oceans in war.
The chief of the Royal Australian Navy and soon-to-be chief of the defence force, Vice Admiral Mark Hammond, brought the SSN into the picture in a discussion of multi-domain deterrence at the ASPI Defence Conference on 25 June.
For those that don’t know, nuclear-powered submarines have really only been involved in combat operations twice. First time, 1982 Falklands War, [when the Royal Navy’s] HMS Conqueror sank the Argentinian Navy’s flagship, the cruiser the General Belgrano, with a spread of straight-running torpedoes. After that engagement, the Argentine surface navy did not come back to sea.
The vice admiral continued:
More recently, earlier this year, one US nuclear-powered submarine [sank] an Iranian frigate. On completion of that engagement, the other Iranian surface combatants that were in the Indian Ocean went alongside in the neutral ports and they’ve stayed there.
And he finished by saying:
The disproportional impact of a nuclear-powered submarine in combat is remarkable. It is extremely difficult and extremely expensive to neutralise, let alone locate. So, in the context of a strategy of denial for an island nation whose approaches require traversing the oceans, it is an extremely important deterrent capability. What it says is, ‘If your determination is to approach Australia’s coast with lethal intent, we will have the capability to deal with it.’
Australia’s acquisition of conventionally armed but nuclear-powered submarines under the AUKUS Pillar One Optimal Pathway will dramatically enhance Defence’s ability to undertake a strategy of denial as laid out in the 2026 National Defence Strategy. The Optimal Pathway will see Navy receive a potent fleet of SSNs – first three Virginia-class SSNs in the 2030s (potentially two more later) and then submarines of the SSN-AUKUS class beginning in the 2040s. Australia’s SSN-AUKUS boats will be built at Osborne in South Australia. The transition to SSNs will enhance the Royal Australian Navy’s ability to create uncertainty for an adversary seeking to project power against our continent and thus enhance the Australian Defence Force’s ability to undertake denial.
The ability of Australia’s SSNs to hold at risk adversary naval forces, on or below the surface, increases the potential cost to any would-be aggressor. Any adversary would have to run a gauntlet of lethal firepower if it sought to deploy forces into Australia’s air and maritime approaches. The SSNs would be combined with other means of long-range power projection, including long-range strike delivered by the Royal Australian Air Force, possibly Australian Army littoral operations, support by sovereign space capabilities, as well as the navy’s surface combatants.
Last year’s deployment by China of two naval task groups – the first of which circumnavigated Australia and conducted unannounced live fire exercises in the Tasman Sea, off Australia’s coast – was a clear signal of Beijing’s intent to project military power against us. It highlighted the risk of failing to deter through denial and highlighted the need to have the ability to defeat such a deployment in wartime.
There is also a risk that an adversary could instead choose to coerce Australia at a distance, by threatening our economic lifeline to the world along maritime trade routes.
Once again SSNs can play a key role in meeting this challenge. While SSNs are not, by themselves, a complete solution, they exploit the benefit of high-speed transit, far greater manoeuvrability and speed in any tactical engagement in comparison with diesel-electric submarines such as the Collins class boats, and much greater endurance on station. They will be well equipped to support maritime surveillance and exploit secure communications to provide information to other ADF units operating in the air and maritime domains, or ashore as part of a joint and integrated force. An ability to work in cooperation with semi-autonomous uncrewed submarines, such as Ghost Sharks and Speartooths, allows SSNs to play a key role in countering adversary efforts to threaten our vital sea lanes – or indeed, to disrupt any attempt to attack submarine cables running through maritime chokepoints.
Opponents of AUKUS choose to ignore the operational and tactical benefits offered by SSNs being introduced under the Pillar One Optimal Pathway and the key role that SSNs will play in supporting both a strategy of denial and helping to defend our vital sea lanes of communication. Yet, given Australia’s vast maritime environment, the case for SSNs is very clear. Once again, Hammond put it well at the conference:
Again, if I go back to the conventionally armed nuclear-powered submarine, that can be anywhere. It can be anywhere really quick. But that in itself is not sufficient. It’s why we’re pursuing the uncrewed underwater vehicles as well, things like Ghost Shark, which in numbers can be everywhere else that matters.
So, having that balance of responsiveness at speed in the most survivable of capabilities available to us, backed up by mass and uncrewed systems capable of doing the dangerous, the dirty and the dull missions, it is absolutely important, especially given that we are the custodians of the third largest exclusive economic zone in the world and we are both the beneficiaries of and somewhat constrained by the most extreme maritime approaches on the planet.
