Could Japan end up provoking the most serious national security crisis yet faced by President Obama?

That idea would have sounded preposterous a couple of years ago, when the Land of the Rising Sun was still the country that Americans have known it to be for the past two decades: gently aging; rich but stagnant; democratic but, because of chronically weak leadership, a non-factor in global and even regional security.

Japan, however, has a history of long periods of stagnation followed by bursts of rapid and sometimes disruptive change. Some who watch the country believe that Shinzo Abe, the conservative nationalist who became prime minister 14 months ago, is leading it into one of those dynamic and potentially dangerous eras.

In his first year in office, Abe successfully stimulated the economy, cultivated Japan’s neighbors and pursued closer security relations with the United States. His first steps to strengthen Japan’s defense posture, such as increasing the arms budget and creating a national security council, looked sensible in the face of increased belligerence from China and North Korea.

In the past several months, however, Abe has appeared to pivot toward the hard-line nationalism that has always been an element of his political makeup. He has managed to set off alarm bells not only in predictable places — China and South Korea — but inside the very U.S. administration he hoped to partner with.

The prime minister’s most conspicuous gesture was his visit on Dec. 26 to the Yasukuni shrine in Tokyo, which memorializes Japanese military dead, including convicted war criminals from World War II. It was an act sure to escalate already considerable tensions with China, which a month earlier had unilaterally declared an air defense zone covering territory claimed by Japan, and it was undertaken with express disregard for high-level appeals from the Obama administration.

That same month Abe appointed four new directors to the 12-member board of Japan’s public broadcast network, NHK. They soon began making headlines. One declared that the 1937 Nanjing massacre by Japanese soldiers in China “never happened” and that U.S. trials of Japanese war criminals were staged to cover up U.S. crimes. A second was revealed to have authored an essay claiming that, thanks to a ritual suicide by a right-wing militant, the Japanese emperor had become a deity.

Then there is the new head of the network, Katsuto Momii, who after belittling Japan’s history of enslaving “comfort women” said during his first news conference that NHK should not criticize the government on subjects such as nuclear power or Abe’s Yasukuni visit.

Momii was obliged to issue a partial retraction and Abe declared his support for media freedom. Days earlier, however, Abe gave a speech at Davos saying that Japanese-Chinese relations faced a “similar situation” to that of Britain and Germany prior to World War I.

In the furor over all this, Japan’s ambassador to Washington, Kenichiro Sasae, made one undeniable point: “It is not Japan that most of Asia and the international community worry about,” he wrote in a Post op-ed. “It is China.” Apart from the Koreas, that is true enough. But Abe’s turn toward nationalism has made an Asian security crisis more likely, for three reasons.

First, the Yasukuni visit has destroyed any possibility of détente in Tokyo’s frozen relations with Beijing and Seoul. Both Chinese president Xi Jinping and South Korean president Park Geun-hye refuse to meet Abe. Diplomatic and military contacts between Japan and China are virtually nonexistent, which is alarming in view of the ongoing dispute over a group of uninhabited islets that both nations claim.

Second, Yasukuni and its aftermath have also badly damaged relations between Abe and the Obama administration. One informed observer says a communications gap has opened up between Washington and Tokyo more profound than that even with Beijing. U.S. officials believe they can no longer be sure of what Abe might do if tensions spike over the islets, or whether he would heed U.S. counsel in a crisis. It doesn’t help that there are virtually no officials at a high level in the White House or State Department who have experience or close relationships with Japan.

The first two troubles lead to a potential third: that Chinese leaders will be moved by their animus toward Abe and their perception of a gap between him and Obama to provoke a test of strength. What if Beijing were to deploy a flotilla of fishing boats around the rocks, or land a company of soldiers on them? Would Abe seek to invoke the U.S.-Japan defense treaty? If he did, would Obama step up — or back?

The president is scheduled to visit Japan in April as part of an Asia tour. Though it won’t be on the official agenda, crisis prevention will be a big part of his mission.

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