TOKYO — Four Japanese cabinet ministers, including a rising political star seen as a potential prime minister, marked the 75th anniversary of World War II’s end on Saturday by visiting Yasukuni Shrine, a memorial with strong links to Japan’s imperial past.
The shrine in Tokyo, which honors Japan’s war dead — including Class A war criminals from the World War II era — is revered by Japanese conservatives. But official visits to the shrine have been highly contentious in Japan and elsewhere in Asia, where the history of Japan’s empire-building in the first decades of the 20th century is still debated.
China, which Japan invaded, and South Korea, which was a Japanese colony for decades, have strongly objected to such visits. The South Korean Foreign Ministry expressed “deep disappointment and concern” over the ministers’ visits to Yasukuni on Saturday, urging Japan to “look squarely at history” and to show “sincere remorse through action.”
Prime Minister Shinzo Abe has not visited the shrine since 2013, when he was criticized for doing so not only by Beijing and Seoul, but by Caroline Kennedy, then the American ambassador. But he sent a ritual offering to Yasukuni on Saturday.
The best-known of the four ministers who did visit was Shinjiro Koizumi, 39, whose father, Junichiro Koizumi, was a popular prime minister, and who has been seen as a potential candidate for that office himself.
Shinjiro Koizumi, currently the environment minister, has been making efforts to distinguish himself as a young, modern politician in the governing Liberal Democratic Party, which is known for conservatism and hewing to tradition. He made headlines early this year by taking paternity leave — a rarity in Japan — and has said that he wants to mobilize young people to fight climate change by making the cause “sexy” and “fun.”
In addition to Mr. Koizumi, Koichi Hagiuda, the education minister; Seiichi Eto, the minister in charge of territorial issues; and Sanae Takaichi, the internal affairs minister, visited the shrine.
Analysts said the visits by four ministers — the most to visit Yasukuni on the anniversary of the war’s end since Mr. Abe came to power in 2012 — could represent a geopolitical message, at a time when China has been flexing its military muscles in the South China Sea and sending provocative patrols near the disputed islands known in Japan as the Senkakus.
“I don’t think it’s a coincidence that you’re getting this number at this moment,” said Tobias Harris, an expert on Japanese politics at Teneo Intelligence in Washington. “It’s hard to see that unconnected from the regional situation.”
But for Mr. Koizumi, analysts said, the visit was also a signal to his domestic political constituency as he seeks to establish his credentials with the right wing of the Liberal Democratic Party, which Mr. Abe leads.
Mr. Abe has long pursued a campaign to move Japan beyond its postwar pacifism. One of his most cherished goals is to revise the clause in the Constitution, enacted by American occupiers, that requires Japan to renounce war, and to build a more powerful country with more normalized military capabilities. Now, as Mr. Abe nears the end of his time in office, potential successors are jostling for position.
The right wing of the Liberal Democrats can wield the power to name future leaders of the party. Though Mr. Koizumi is likely to be seen as too young to be Mr. Abe’s immediate successor, he may be laying groundwork for support later on.
“In order to be progressive in social and environmental policy, he cannot be seen as a cold- blooded city liberal who doesn’t care about the rest of Japan,” said Lully Miura, a political scientist who runs the Yamaneko Research Institute in Tokyo. “His enemies are domestic rather than foreign. That’s why he didn’t hesitate to visit the controversial Yasukuni Shrine.”
Conservative Liberal Democrats have previously sought to revise historical accounts of Japan’s atrocities during the war, and visits to Yasukuni can signal sympathy with those efforts, as well as defiance of international criticism.
Naoki Hyakuta, a conservative author, wrote on Twitter that even if Mr. Koizumi’s Yasukuni visit was a “performance,” it showed “a resolute declaration that Japan will not accept interference in international affairs by China.”
Mr. Koizumi has gone to the shrine every year since being elected to Parliament, but this was his first visit as a cabinet minister. His father paid six visits to Yasukuni during his time as prime minister.
Junichiro Koizumi, who was prime minister and leader of the Liberal Democrats from 2001 to 2006, was a maverick who defied the party’s right wing. He tried to reform the powerful post office and revise the Imperial Household Law to let women inherit the Japanese throne (that effort failed). But his repeated visits to Yasukuni shored up his support among conservatives who opposed those campaigns.
“This reformist, iconoclastic image went hand in hand with visits to Yasukuni,” said Koichi Nakano, a political scientist at Sophia University in Tokyo. “So I am guessing Shinjiro is thinking the same.”
Critics of Mr. Koizumi asked why he was visiting Yasukuni instead of Mauritius, where a Japanese-owned ship recently caused an environmental disaster by spilling 1,000 tons of fuel oil into the sea.
“He went to Yasukuni?” wrote one Twitter user. “I think he should now learn and lead with action as environment minister. He has a child, right? The ocean is connected.”
Mr. Koizumi told reporters on Saturday that his ministry would send a team of specialists to investigate the damage in Mauritius. According to the news agency Reuters, he described the oil spill as a grave crisis that could lead to a loss of biodiversity.
Mr. Abe, who has recently dialed back his public appearances, sent a ritual offering of cash to Yasukuni on Saturday, as well as flowers to be laid at a cemetery near the shrine.
In a speech at a Tokyo ceremony commemorating the end of the war, Mr. Abe said: “Under the flag of proactive pacifism, by holding hands with the international community, we are determined to play a role more than ever to resolve various challenges.”
Emperor Naruhito, appearing with his wife, Empress Masako, also addressed the ceremony, expressing “feelings of deep remorse” for the war.
In using those words, he continued a tradition begun by his father, Akihito, who abdicated last year. Akihito added that phrase to his annual remarks in 2015, after Mr. Abe pushed through legislation that opened the door to letting the Japanese military fight in foreign conflicts.
Hisako Ueno contributed reporting from Tokyo and Choe Sang-Hun from Seoul, South Korea.