The Optimal Pathway announcement, made on March 14, 2023, (13 March US time) marked a significant milestone in Australia’s defense strategy. Over the past two years, the AUKUS defense and security partnership has led to substantial domestic and international advancements, enhancing Australia’s defense capabilities and strengthening its strategic partnerships.
The AUKUS Optimal Pathway is Australia’s plan to acquire nuclear-powered submarines, modernizing its defense capabilities for the Indo-Pacific. These state-of-the-art submarines will offer unmatched stealth, speed, and endurance; ensuring Australia can support regional security and maintain a cutting-edge technological edge in an increasingly complex global landscape.
Domestically, the Optimal Pathway’s profound impact on Australia’s defense industry and workforce, and is expected to create around 20,000 direct jobs over the next 30 years. The Australian Government will invest in additional training, skilling and educational programs to achieve this growth for Australia’s local submarine and shipbuilding industry. Over the next four years, the phased approach will result in a multi-billion dollar investment in Australia’s industrial capability and workforce to build a future made in Australia by Australians.
Through the Optimal Pathway, the Australian Submarine Agency (ASA) has commenced the development of significant infrastructure upgrades in South Australia with the expansion of the Osborne Submarine Construction Yard, a key facility for the construction of nuclear submarines. These upgrades are essential for supporting the construction of nuclear-powered submarines and ensuring the long-term success of Australia’s submarine program. Additionally, the commitment from the Australian Government will see $2 billion invested into South Australia and a further $1 billion in Western Australia over the next four years. These investments will enhance the infrastructure necessary for the construction and maintenance of nuclear-powered submarines.
The ASA has also facilitated significant industry collaborations. In March 2024, Australia selected ASC Pty Ltd and BAE Systems to build its SSN-AUKUS submarines. ASC was also announced as Australia’s nuclear-powered submarine sustainment partner. These industry partnerships are vital for leveraging the expertise and capabilities of leading defense contractors in Australia and the UK to support Australia’s submarine program. Further developing the industrial base for a nuclear‑powered submarine capability will require a complex and consequential industrial transformation to Australian defense industry, supported by the recently launched Australia’s AUKUS Submarine Industry Strategy on 5 March 2025.
In terms of workforce development, the ASA has facilitated the training and integration of Australian personnel into the maintenance of US nuclear-powered submarines. This integration and partnership was seen up-close during the August 2024 Submarine Tendered Maintenance Period (STMP), when USS Hawaii, a Virginia class submarine, came into port at HMAS Stirling. Along with the USS Hawaii, the STMP also involved the US tender ship, the USS Emory S Land, which had more than 30 Royal Australian Navy personnel embedded for a period of 6 months to learn the maintenance skills required to conduct work on nuclear-powered submarines. The STMP was the first time Australian personnel have directly participated in such maintenance activities on Australian soil, and marked a major milestone on the Optimal Pathway.
Ongoing port visits – like the USS Minnesota docking at HMAS Stirling on 25 February this year – help Australia and AUKUS partners prepare for the start of Submarine Rotational-Force West at HMAS Stirling from as early as 2027. The Submarine Rotational-Force West will see one UK Astute class submarine and up to four US Virginia class submarines having a rotational presence at the base.
In January 2025, the trilateral AUKUS Naval Nuclear Propulsion Agreement (ANNPA) entered into force. This Agreement enables the continued sharing of naval nuclear propulsion information and allows for the transfer of nuclear material and equipment from the UK and the US to Australia. The ANNPA also reaffirms and is consistent with the AUKUS partners’ respective international legal obligations and Australia’s safeguards agreements with the International Atomic Energy Agency.
Australia’s and AUKUS partners’ commitment to setting the highest non-proliferation standard remains a key focus of the Optimal Pathway.
Australia is unwavering in its commitment to safely and securely steward its nuclear-powered submarines through their entire life cycles. In doing so, Australia will build on the UK and US’s 70-year unblemished track record of safely operating other nuclear facilities and conducting nuclear science activities. It will also draw on their decades of experience and world-leading expertise in delivering, operating and maintaining nuclear-powered submarines.
The past two years since the Optimal Pathway announcement have been marked by significant achievements for Australia, both domestically and internationally. From workforce development and infrastructure projects; to industry collaborations and adherence to non-proliferation standards, Australia has made remarkable progress in its journey to acquire and operate conventionally armed, nuclear-powered submarines. As the Optimal Pathway continues to evolve, Australia remains steadfast in its mission to deliver a world-class nuclear-powered submarine capability and contribute to regional security and stability.