Tokyo, July 15, 2025 — In its 2025 Annual Defense White Paper, Japan has officially designated China’s expanding military maneuvers—from its southwestern coast through the Pacific—as the nation’s most critical strategic challenge .

Key Findings of the Defense White Paper

• Escalating military presence: The report highlights a significant increase in Chinese naval and air activity near Japan—warship transits have tripled, including aircraft carrier patrols in the Pacific Wall Street Journal+15AP News+15Houston Chronicle+15.
• Growing regional alliances: Japan warns of China’s deepening military ties with Russia and mounting tensions around Taiwan, alongside new missile threats from North Korea BBC+12AP News+12Politico+12.
• Historic gravity: Authorities declare this era to be “the biggest challenges since the end of World War II,” marking a steep deterioration in global power dynamics Business Standard+2Politico+2朝日新聞+2.

Tokyo’s Strategic Response

• Military reinforcement: Japan is fortifying its southwestern islands and accelerating deployment of long-range cruise missiles as a deterrent against potential conflict over Taiwan Wall Street Journal+9AP News+9Politico+9.
• Airspace vigilance: The defense ministry continues to challenge close-proximity Chinese fighter jet encounters, citing “dangerously close” aerial maneuvers AP News+12AP News+12朝日新聞+12.
• Strengthening U.S. alignment: Japan is aligning more closely with U.S. Indo-Pacific strategy, preparing to assume more direct security responsibilities amid shifting American policy theguardian.com+2Reddit+2Reddit+2.

Broader Regional Context

Threat Actor	Nature of Concern
China	Sea and air patrols near Okinotorishima and Yonaguni; aircraft carrier drills; and long-distance bomber flights Houston Chronicle+3Wikipedia+3Business Standard+3.
North Korea	Advancing its nuclear-capable missile program—highlighted as a “more grave and imminent threat than ever” .
Russia	Increased military activities in proximity to Japan, including past airspace violations and collaborative drills with China .

Strategic Takeaway

This year’s report marks a notable shift in Japan’s defense posture. With China’s security stance now at the forefront, Japan is committing to deeper defense investments, expanding missile and air capabilities, and enhancing readiness in the contested southwestern island chain.

The document’s strong tone sends a message not only to Beijing, but to allies and partners: Japan intends to take a far more assertive role in Indo-Pacific security, even as it maintains its constitutionally constrained stance on self-defense.