Chinese military hackers have been accessing Japan's classified defence networks since 2020, gaining access to information on US military capacities, plans, and evaluations of deficiencies, the Washington Post has reported citing senior officials. The following day, Japan said it could not confirm whether any security information had been leaked, although Japan and the USA have always maintained close exchanges at multiple layers.

The Director of the National Security Agency of the US (NSA) was said to have travelled to Tokyo after learning of the hack to brief the Japanese defence minister. Both sides eventually agreed to hire a Japanese commercial firm to examine the vulnerabilities, with the US NSA/Cyber Command team to vet the firm's findings and recommend how to address any gaps.

It is reported that the hacking began under the Trump administration and continued under the Biden administration. Evidence also showed continued breaches of Japan's defence systems and no progress in stopping the leaks.

At a regular press briefing on Tuesday, Japan's Chief Cabinet Secretary, Hirokazu Matsuno, said that cybersecurity is the foundation for maintaining the US-Japan alliance and that Japan will continue to work to keep its network strong and secure.

Why does it matter?

Although the hack technically dates back to 2020, this news arrives amidst escalating tensions between China and the US in cyberspace, as both sides trade accusations of hacking for military intelligence acquisition. Among them: US claiming that a China-based threat actor attempted to access email systems to gather US intelligence, China claiming US hackers breached Wuhan earthquake monitors to spy on China's military operations and US officials claiming that China is hiding malicious code in networks controlling vital utilities for military bases. The news might also mean that security information exchanges between Japan and the USA might slow down.