Australian Naval Institute – Guided by Geoffrey Till’s emphasis on naval balance and freedom of navigation^[i], this essay argues that China’s expanding naval posture near Australia signals a contested transition from Pax Americana to a prospective Pax Sinica. The analysis evaluates the broader implications for Canberra’s alliances, strategic autonomy, and regional security and considered whether these developments represent a natural recalibration of great-power behaviour or a deliberate challenge to Australia’s sovereignty.