China is leaning harder on World War II history as a political weapon to weaken Japan's standing on Taiwan security, and this is bad news for Japan-China relations and a warning sign for Taiwan.

• Beijing has sharply increased its use of anti-Japan war history, including a national memorial day for the Nanjing massacre and rewriting textbooks to stretch the "war of resistance" from eight to fourteen years.
• Scholars say this push intensified after Japan's prime minister raised the idea that a Taiwan crisis would be a crisis for Japan too, prompting China to link Japan more directly to the Taiwan issue for the first time.
• The strategy aims to paint Japan as an unrepentant former aggressor trying to meddle in Taiwan again, undercutting Japan's legitimacy to weigh in on regional security.
• This marks a shift from Mao-era China, which downplayed the same history and even credited Japan's invasion with helping the Communists win power — showing Beijing bends its history narrative to fit current political needs.
• Analysts see this as proof that China now views Japan, alongside the US, as a country it must directly contend with over Taiwan, effectively internationalizing the Taiwan issue further.

Outlook: Expect China to keep using historical grievance as a pressure tactic against Japan as tensions over Taiwan and US-Japan security ties continue to build.