Japan's defence minister visited a controversial war shrine in Tokyo Thursday, the day after she paid a highly symbolic visit to Pearl Harbor with Prime Minister Shinzo Abe, media reports said.
Television footage showed Inada visiting Tokyo's Yasukuni Shrine, which honors Japanese who lost their lives in the country's wars, including several leaders executed for war crimes.
Japanese leaders have visited Pearl Harbor before, but Abe was the first to go to the memorial above the sunken USS Arizona, where a marbled wall lists the names of US troops killed in the Japanese attack.
"Japan and the United States, which waged the harshest battles, are now in the strongest alliance relationship", Inada told reporters after the visit.
Inada did not pay a visit on the August 15 anniversary of Japan's surrender in World War II due to her four-day trip to Djibouti to inspect Self-Defense Forces troops engaged in an antipiracy mission off Somalia.
China's foreign ministry summoned the Japanese embassy minister in Beijing, Koichi Ito, to lodge an official protest over Inada's visit.
Abe has fought a battle to reform national security laws in order to amend a section of Japan's pacifist constitution and expand the external powers of the Japan Self-Defence Forces (the Japanese military). Late last week, the Liaoning advanced into the western Pacific after passing the so-called "first island chain", a sea defense line China unilaterally draws running from southern Japan to Taiwan, the Philippines and the southern South China Sea.
Abe, who became Japan's first leader to visit Pearl Harbor with a USA president, said the visit "brought utter silence to me".
Anger toward Japan runs deep in both countries, where many feel that Japan has not fully atoned for their brutal behavior during World War II. As an MP she had made the trip every 15 August - the anniversary of Japan's wartime defeat - between 2006 and 2015.
A Chinese Foreign Ministry spokeswoman, Hua Chunying, said his visit "reflects the Japanese government's unhealthy attitude toward its past transgressions". Especially sensitive in China is the sack of Nanking, where hundreds of thousands of Chinese are believed to have been killed and raped during the Japanese army's vicious 1937 attack. The ministry also said in a statement earlier that it was "deplorable that a responsible Japanese politician worships at Yasukuni Shrine, which beautifies past colonial invasions and invasive wars, and enshrines war criminals".