China’s move toward an all-nuclear submarine fleet could extend its strategic reach from the Pacific to the Indian Ocean by prompting a broader regional buildup of nuclear-powered underwater forces.
This month, the chief of US naval intelligence, Rear Admiral Mike Brookes, TESTIFIES before the US-China Economic and Security Review Commission (USCC) that China is undertaking a major shift toward building an all-nuclear submarine fleet as part of a broader effort to strengthen its underwater warfare capabilities and expand its blue-water naval power.
According to Brookes, the People’s Liberation Army Navy (PLAN), which operates more than 60 submarines in total, including approximately 50 conventional diesel-electric boats (SSK) and a smaller number of nuclear-powered attack submarines (SSN) and ballistic missile (SSBN), is moving from a conventional nuclear program to a transitional submarine program. support sustainment operations, strategic deterrence and interdiction of sea lanes.
He notes that this change marks a fundamental departure from China’s previous reliance on large numbers of conventional submarines, reflecting the view that nuclear propulsion offers greater operational durability, range and flexibility to compete with US and allied navies.
Brookes also says China has expanded its submarine manufacturing infrastructure at three major shipyards, tripling building hall capacity and more than doubling production capacity to sustain higher production of advanced nuclear-powered vessels until the 2030s.
He mentions that a new class of smaller nuclear attack submarines sometimes referred to as the Type 041 “Zhou-class” is being developed to perform patrol missions and regional presence at lower cost than larger attack submarines.
At the same time, the next-generation Type 095 SSGN and Type 096 SSBN expected in the late 2020s and 2030s will include quieter reactors, improved sensors, and longer-range submarine-launched ballistic missiles (SLBMs), enabling China to retain water defenses from closed homes. says.
Despite these advances, China may still face challenges in growing its nuclear submarine manufacturing base.
As Sarah Kirchberger notes in a September 2023 REPORT for the China Maritime Studies Institute (CMSI), China’s submarine industrial base still faces significant technological challenges in propulsion systems and acoustic quietness, areas in which Western and Russian submarines remain more advanced.
She notes that Chinese engineers have struggled with vibration suppression, noise reduction and sound-absorbing coatings, factors that contribute to relatively higher acoustic signatures.
However, an all-nuclear submarine fleet could give China the ability to escort its carrier strike groups (CSGs) in the Pacific, threaten US carriers operating beyond the First Island Chain to deter US and allied intervention in the event of a conflict over Taiwan, and enable continuous SSBN patrols within China’s heavily defended nuclear capability in basketball.
Beyond these applications, an all-nuclear submarine force could project China’s power into the Indian Ocean. China can use nuclear submarines to threaten India’s sea-based deterrence. China and India have long-standing border disputes in the Himalayas, marked by skirmishes and the potential for full-scale conflict between the nuclear-armed states.
According to a March 2025 Nuclear Threat Initiative (NTI) REPORTIndia plans to deploy four Arihant-class SSBNs, with the flagship, INS Arihant, armed with 12 Sagarika submarine-launched ballistic missiles (SLBMs) with a range of about 700 kilometers – limited to targets in western or southwestern China in the protected bastions of Bengal.
However, the NTI report notes that Arihant’s successors, including INS Arighat, could be armed with longer-range K-4 SLBMs with a range of approximately 3,500 kilometers, enabling strikes against targets deep inside China’s territory.
Therefore, China can use its SSNs to shadow India’s SSBNs in the Bay of Bengal, Like the US Navy’s SSNs possibly overshadowing China’s SSBNs in the South China Sea.
Highlighting this possibility, in 2013, a Chinese SSN completed a patrol in the Indian Ocean and sailed to the Gulf of Adenshowing the durability needed for long-range patrols in regions with limited supply options.
However, China faces geographic barriers to access the Indian Ocean, requiring passage through strategic chokepoints such as the Malacca, Lombok, Sunda and Ombai Straits.
The shallow depth of the Straits of Malacca and the heavy traffic complicate the clandestine transit of submarines. The Sunda Strait’s even shallower depth, strong currents, and obstacles such as sandbars and oil rigs make passage difficult. While the Lombok (~250 meters deep) and Ombai (~3,000 meters deep) straits allow submerged passage, limited hydrological data complicates navigation.
China’s push for an all-nuclear submarine fleet could prompt similar efforts in India and other Pacific nations such as Japan, South Korea and Australia.
Similar to China, India’s future Project 77 SSNs can escort its SSBNs to its bastions in the Bay of Bengal, escort its CSGs in the Indian Ocean, support long-range strike operations with submarine-launched cruise missiles, and deter adversaries from deploying Indian naval forces in the Indian Ocean.
Besides India, Japan and South Korea may take note of China’s efforts to build an all-nuclear submarine fleet. As noted by John Bradford and other writers in November 2025 REPORT for the S. Rajaratnam School of International Studies (RSIS), Japan and South Korea are reconsidering their long-standing reliance on advanced conventional submarines amid a deteriorating regional security environment and expanding military capabilities among potential adversaries.
Bradford and others note that Japan and South Korea are exploring nuclear-powered submarines because they offer speed, endurance and greater operational flexibility for long-range patrols and sea-lane defense. However, they note that cost, manpower requirements and political constraints remain major obstacles.
On South Korea, Bradford and others say the country faces fewer domestic political barriers but must resolve nuclear fuel restrictions under its 2015 agreement with the US. As for Japan, they say it must overcome domestic opposition to the military use of nuclear technology before pursuing such submarines.
In Australia’s case, the future of its AUKUS nuclear submarine program with the US and UK appears uncertain.
A January 2026 US Congressional Research Service (CRS). REPORT outlines an alternative arrangement in which the US could retain additional Virginia-class submarines rather than sell three to five boats to Australia, with the US submarines operating from Australian bases and performing missions that would otherwise be undertaken by Australian SSNs.
Under this approach, the report says, US and UK nuclear submarines would still circle Western Australia, while Australia could focus resources on other capabilities that support the alliance.
If China eventually succeeds in creating a fully nuclear-powered submarine fleet, it could shape not only the future balance of undersea power in the Indo-Pacific, but also trigger a broader regional competition under the waves as rivals adapt their submarine strategies in response.
