Last October, while staring down Congress over the federal government's partial shutdown, President Obama scuttled a planned trip to Asia — a quickly forgotten footnote in America. But from Tokyo to Bangkok, Obama's no-show was a front-page, newscast-leading disappointment. It's a measure of how easily we Americans, for all our overweening pride, underestimate and misunderstand our nation's importance in the world.

This week, Obama will at last move his diplomatic "pivot to Asia" from rhetoric to reality as he visits Japan, South Korea, the Philippines and Malaysia. He will encounter a worried region, haunted by a tragic past and tense in the face of a troubled present, and much in need of reassurance.

That was the clear consensus from experts in and out of government whom I interviewed on a March trip to Tokyo and Hiroshima that was coordinated by the independent Foreign Press Center of Japan. In dozens of discussions, the consistent theme was that America's pivot can't come soon enough.

"The government of Japan very much welcomes the pivot policy of the Obama administration," said Hirotaka Ishihara, parliamentary vice-minister for foreign affairs. Yasuhiro Kobe, director of the Japan-U.S. Security Treaty Division at the Ministry of Foreign Affairs, added that "the security situation surrounding Asia has been becoming tougher, and in that sense we need more presence and more deterrence by U.S. forces in the region."

The call for "more presence" may in part be a polite plea for something more. The West's tepid response to Russian aggression in Crimea makes many wary in Japan. So does a perception that Obama was unserious about Syria's chemical weapons attack.

"The Obama administration is not doing such a good job maintaining its credibility — it undermined it for no good reason," said Dr. Narushige Michishita, director of the Security and International Studies Program at the National Graduate Institute for Policy Studies. Obama's blurred "red line" was read in Asia as "a lack of commitment, determination, coherence and consistency. … If you are a superpower symbolism is very important."

American credibility is crucial to a worried Asia, contending with the threat of a nuclear North Korea and the challenge of China's emergence as a global power. Every signal matters.

"The rise of China and the relative decline of the U.S. and Japan and the regional power shift going on is causing a lot of trouble, and is the fundamental reason why this region is becoming quite tense," said Michishita.

Tensions run particularly high around the East China Sea. In a November decision that stunned the region and the United States, China unilaterally declared an Air Defense Identification Zone over disputed, uninhabited islands that both Japan and China claim. The ADIZ covers airspace claimed not just by Japan, but by South Korea and Taiwan as well.

While the United States hasn't taken a stand on ownership, its stand with Japan via a defense pact might compel military involvement for U.S. forces if China miscalculates. In February, it was reported that the U.S. Navy believes China was preparing for a "short sharp war to destroy Japanese forces in the East China Sea."

"China is increasing its power and sometimes they have tried to change the status quo with possible use of force," said Kenko Sone, director of the First North America Division at the Ministry of Foreign Affairs.

Rethinking the constitution

But China is hardly the only Asian power whose perceived muscle flexing unnerves its neighbors. Another is … Japan. Memories of World War II, which may be fading in America with the aging and passing of the G.I. generation, are painfully alive in Asia.

Many in China and across the continent who suffered under Japan's brutal wartime occupation worry that Tokyo might also alter the regional status quo if Japan reinterprets its postwar constitution to allow for what's called collective self-defense. It basically means that Japanese armed forces could act jointly with allies in the event war was forced upon it.

The United States imposed the pacifist provision of Japan's constitution after the war. But today American officials support Japan's public mulling of whether to reinterpret it, or even revise (amend) it. And Prime Minister Shinzo Abe's government seems to believe that such a shift might be a stabilizing, not destabilizing, event for the region.

"Whatever we do will be an extension of our principle as a pacifist, peace-loving nation," said Ishihara, the parliamentary vice-minister. "We will continue to provide transparent, elaborate explanations in order for [neighboring nations] to understand and support." Describing a hypothetical situation in which Japanese peacekeeping troops, under the constitution as currently understood, could not come to the aid of U.S. forces under attack, he said such a limitation "runs counter to global common sense."

Michishita agrees, but he favors formal revision, not reinterpretation, in order to preserve the constitution's credibility. He believes Japan owes a new more self-reliant posture to its allies, under whose military umbrella the nation has lived for seven decades. "We have been living in this very comfortable and convenient situation," he says. "Unless we do this, we will continue to get criticism that Japan is a free rider."

That's not the criticism coming from Japan's Asian neighbors, however. Generations after the war, history — and in some cases, histrionics — have renewed anger at Japan. Chinese officials have ratcheted up the rhetoric, and in South Korea the emotional debate is over "comfort women" — South Korean women and girls who were forced into prostitution by occupying Japanese forces.

"We have repeatedly expressed our feelings of deep remorse and heartfelt apologies," said Ishihara. It's not only Japan that's trying to close the reopened wounds. Obama hastily arranged a meeting between Abe and South Korean President Park Geun-hye at the recent nuclear security summit at The Hague.

But Japanese feelings about the past are complex. Japan's top box-office hit earlier this year was "The Eternal Zero," a sympathetic portrait of a Kamikaze pilot. A more heated national conversation — and international condemnation — was sparked when Abe made a pilgrimage to the Yasukuni Shrine, where war dead, including 14 "Class-A war criminals," are memorialized. Along with sharp rebukes from China, South Korea and other nations that suffered under Japan's cruel occupation, the visit even drew criticism — or a frank exchange, in diplomatic parlance — from the United States.

Visiting on a drizzly day, I found the Shinto shrine more somber than martial — at least compared to the adjoining museum, which displayed a gleaming Zero among other Japanese military artifacts.

Regardless, Abe made a mistake with his visit, enflaming an already tense situation.

Self-described foreign-policy "realists" like Michishita thought it ill-advised, too. He describes two schools of thought in Japan over re-examining the nation's role in the world.

One group, he says, wants a pacifist, even isolationist nation that focuses on economic revival. After all, most are still suffering from Japan's so-called "lost decade" of deflation, described as "not so much an economic phenomenon as a psychological one" by Tomohiko Taniguchi, who advises Abe on economics as a member of the Cabinet Secretariat.

The other group urges a growing global role, Michishita said. But he added that a split within the latter cohort is crucial, with each subset favoring reinterpretation of the constitution, but for different reasons.

"Internationalists" want to see Japan become more of a full partner within the international community and multilateral institutions. "Nationalists" want a more assertive and less apologetic Japan, based on a more patriotic sentiment.

Abe, he believes, belongs to the second group.

Long view from Hiroshima

In Hiroshima, a different kind of shrine tells a different kind of war-era story. There, the iconic "Atomic Dome," a U.N. World Heritage Site, is one of the few remaining structures from Aug. 6, 1945, bearing witness to the horrors of war gone nuclear. Under gray, solemn skies, the untouched rubble and naked steel girders are somber reminders of a war that still seems to be roiling the region. The dome, and Hiroshima itself, have become global symbols for the nonproliferation movement.

"Hiroshima is a city which has been pulling for the total abolition of nuclear weapons, which are an absolute evil," said Kazumi Matsui, mayor of Hiroshima and president of Mayors for Peace, a global nonproliferation movement whose membership includes St. Paul and Minneapolis. Matsui's a realist about the region and the global proliferation pressures. But he takes the long view — the really long view — when he says that the nuclear age "is such a short moment in the long history of human beings. When more policymakers can build a world on the foundation of mutual trust, then the world will move toward one without nuclear weapons."

The beginning of this "brief moment" changed the long lives of survivors I spoke to. Each told harrowing stories about how as children or young adults they happened to survive a blast that killed most others, and how as adults they have dedicated their lives to abolishing nukes. Each seemed wary, and weary, about the region's renewed bellicosity.

Sunao Tsuboi said that before the war he got "the wrong education" and was a "right-wing person who adored the emperor." Now, the dignified Tsuboi is co-chair of the Japan Confederation of A- and H-Bomb Sufferers Organization. When asked about the constitutional issue, he said, "I want to say 'wake up' to the government." On the region he added that, "Being nationalistic can be dangerous. Everyone has to think about borderless countries."

Tsuboi isn't alone in his idealism, at least in Hiroshima. As opposed to naiveté, it's necessary for some confronted with so many daily reminders of nuclear war. Ironically, their sentiments could be a model for other Asian nations newly enraged over memories of Japan's wartime misdeeds.

"This city was completely devastated," said Mayor Matsui. "We had every right to hold a grudge and hate the ones who did this to us. However, we did not do it. We are showcasing how we can forgive the mistake and be friends. If we can do this, then everyone else can emulate us. It's the mission of the city to keep saying this."

Obama, for his part, will have many missions on this week's trip. He'll try to reassure allies, and to revive the Trans-Pacific Partnership, a proposed 12-nation trade pact that's viewed by many in Japan as not just economic policy, but foreign policy. But as he turns to Asia, Obama's most important mission is to help stop the region from pivoting toward war once more.

John Rash is a Star Tribune editorial writer and columnist. The Rash Report can be heard at 8:20 a.m. Fridays on WCCO Radio, 830-AM. On Twitter: @rashreport.