World

Australia Fortifies Navy Amidst China’s Military Buildup in South China Sea: What’s at Stake?

Australia boosts defense due to China‘s military build-up, protecting sea routes in South China Sea.

November 3, 2025, 11:29 PM

The HMAS Parramatta frigate sails in Sydney Harbour with the iconic shell-like roofs of the Sydney Opera House visible in the background.

The Anzac-class frigate HMAS Parramatta (FFH 154) of the Royal Australian Navy in Sydney. By Ryan Fletcher / Shutterstock.com.

Executive Summary

Australia’s Defense Minister Richard Marles stated that safeguarding vital sea trade routes, particularly in the South China Sea, is becoming increasingly perilous due to China’s “biggest military build-up in the world.”

Australia is significantly increasing its defense spending and naval capabilities, including acquiring frigates, developing advanced submarine drones, and expanding naval shipyards, in response to these evolving geopolitical dynamics.

Marles’ remarks follow a recent incident where a Chinese fighter jet released flares near an Australian maritime patrol plane in the South China Sea, which Australia labeled “unsafe and unprofessional.”

The Story So Far

Australia’s increased defense spending and naval enhancements are a direct response to China’s significant and “unreassured” military build-up, which is making the safeguarding of vital sea trade routes in the South China Sea and East China Sea increasingly perilous for nations like Australia. This strategic shift is further driven by recent “unsafe and unprofessional” maritime incidents involving Chinese forces and Australia’s ongoing commitment to enhancing its long-range naval capabilities, including through the AUKUS security pact, to protect its national interests and ensure regional stability.

Why This Matters

Australia’s declaration of increasing peril in safeguarding vital sea trade routes due to China’s “biggest military build-up” signals a significant escalation in regional tensions, prompting Australia to substantially increase its defense spending and naval capabilities, including acquiring advanced frigates and submarine drones. This strategic enhancement reflects a broader Indo-Pacific effort to counter China’s growing military presence and secure critical maritime arteries, indicating a heightened risk environment for regional stability and international trade.

Who Thinks What?

Australia’s Defense Minister Richard Marles believes China’s extensive military expansion is making the protection of vital sea trade routes in the South China Sea increasingly perilous, necessitating Australia’s significant increase in defense spending and naval capabilities.

China, through its “biggest military build-up in the world today” and actions like releasing flares near Australian patrol planes, is perceived by Australia as creating heightened risk and engaging in “unsafe and unprofessional” conduct in crucial sea lanes.

Australia’s Defense Minister Richard Marles stated on Tuesday that the nation’s efforts to safeguard its vital sea trade routes, particularly through the contested South China Sea, are becoming increasingly perilous. This heightened risk is attributed to what he described as China’s “biggest military build-up in the world today,” prompting Australia to significantly increase its defense spending and naval capabilities. Marles made these remarks at an Indo-Pacific navy conference in Sydney, emphasizing the critical importance of open sea lanes to Australia’s national interests.

China’s Military Expansion and Regional Risk

Minister Marles highlighted that China’s extensive military expansion, occurring “without strategic reassurance,” necessitates a robust response from Australia and other nations in the region. He underscored that the work of protecting crucial trade routes in the South China Sea and East China Sea is becoming more challenging and risky for Australian forces.

Australia’s Defense Strategy

In response to these evolving geopolitical dynamics, Australia is committed to building a “more capable, lethal, long-range navy.” This strategic enhancement includes the acquisition of frigates from Japan, collaboration with the U.S. company Anduril to develop advanced submarine drones, and the expansion of naval shipyards along its Indian Ocean coast.

Recent Maritime Incidents

The minister’s comments follow a recent incident last month where Australia raised concerns with Beijing after a Chinese fighter jet released flares near an Australian maritime patrol plane conducting surveillance in the South China Sea. Australian officials have consistently labeled such encounters as “unsafe and unprofessional.”

Indo-Pacific Conference Context

The Sydney conference is hosting dozens of navy and coast guard chiefs from a range of nations, including the United States, Japan, the Philippines, Singapore, and various Pacific Island states. The event takes place as Australia advances its plans to develop a nuclear-powered submarine fleet through the AUKUS security pact with the U.S. and Britain.

Protests Outside Conference

Outside the conference venue in Darling Harbour, approximately 100 protesters, including pro-Palestinian groups, gathered to demonstrate. New South Wales police reported seven arrests following clashes with officers. Several Israeli companies were exhibiting at the defence event.

Regional Security Implications

The statements from Minister Marles underscore growing regional anxieties over China’s military expansion and its implications for maritime security in the Indo-Pacific. Australia’s strategic pivot towards enhancing its naval power reflects a broader regional effort to manage geopolitical shifts and safeguard critical trade arteries.