A self-defense forces member broke into the Chinese embassy in Tokyo, sparking concerns of rising militarism and anti-China sentiment in Japan.

Japan has moved swiftly to contain the diplomatic fallout after a member of its Self-Defence Forces broke into the Chinese embassy in Tokyo last week. But observers and local media say the incident has given Beijing an opening to reinforce claims of rising militarism and anti-China sentiment in Japan. Yoshinobu Kusunoki, commissioner general of the National Police Agency, on Monday called the break-in on March 24 “extremely unusual and serious”, adding that it “should not have happened”. His...