After their triple-whammy disaster one year ago, many Japanese cycled through emotions familiar to Americans after Hurricane Katrina: disbelief at the failure to anticipate such a crisis, anger at official obfuscation as it unfolded, frustration at the slow pace of reconstruction ever since. The scale of the catastrophe provoked another sentiment Americans will recall: the sense that, after this, nothing will ever be the same.

But there were also differences between the two countries’ reactions. The stark class and racial disparities exposed by Katrina had no echoes in Japan after it was hit by an earthquake, a tsunami and the collapse of a nuclear plant, with the loss of some 20,000 lives (10 times the death toll from Katrina), one year ago Sunday.

And the disaster of 3/11 triggered a profound questioning of the foundations of Japan’s prosperity of a kind Katrina did not evoke.

At a forum sponsored this week by the German Marshall Fund, the celebrated poet Madoka Mayazumi said that the crisis has forced Japan to confront “some basic questions” such as what has been achieved through “the constant pursuit of more.”

“It seems to me that by pursuing this obsession with economic growth and efficiency, the whole world has driven itself into a corner,” she said. “An aesthetic of reduction can be one way to reframe our lifestyle.”

A Tokyo patron of the arts (and old friend of mine), Kazuko Aso, expressed similar thoughts after organizing an exhibition of young artists’ works in response to the crisis. (The art is on display at the Edison Place Gallery in Washington through March 24.)

“This disaster put an end to the era of the post-war prosperity; the time for chasing economic success and materialistic prosperity is over,” Aso wrote in an introduction to the exhibition catalogue. “The disaster has reminded us . . . we can never conquer nature; we must live with it.”

One explanation for this difference in reactions is that Japan’s disaster implicated far more complex technology than the levees that failed in New Orleans: the atomic energy that helped power the phenomenal rise of resource-poor Japan.

Another is that Japan was already in something of an identity crisis when the earthquake struck.

Just a quarter-century ago, Japanese believed they were about to overtake America as the world’s leading economy. That never came to pass, and last year Japan was knocked from its No. 2 perch by China, with a prospect of further relative decline.

In politics, too, the nation was adrift. An upstart left-of-center party had unseated the conservatives who had ruled Japan for more than half a century, but by the time of the disaster — 11 / 2 years into its administration — the Democratic Party of Japan had yet to find its footing.

Most of all, there was the dawning realization that, because of Japan’s pathologically low birth rate and its allergy to immigration, its population would both dramatically age and dramatically decrease in coming decades.

After the initial shock came hope that the disaster would jump-start Japan out of its malaise — that the country would rebound as it had after World War II or the 1973 oil crisis.

But jump which way? For some, the disaster points toward accepting a reduced position for Japan in the world instead of resisting it.

“Our status as an economic power will come down, but look at France or Germany or Great Britain,” Hideki Kato, president of the Tokyo Foundation, said at the forum this week. “The economic scale in Japan is much bigger, but I don’t think the level of happiness is much bigger.”

Others hope Japan’s growth will resume but in a new direction. Just as the Japan of the 1980s proved the possibility of economic power without military might, so in an era of climate change and diminishing resources Japan would blaze a more sustainable path.

And then there are those, like Japan’s savvy ambassador to the United States, Ichiro Fujisaki, who argue that with 127 million people living on narrow, rocky islands, “we have to depend on science and technology.”

“We will seek safe and sustainable technology,” he told me, “but I don’t think it will change our society or makes us less open to innovation.”

In the past year, a new prime minister has provided steadier leadership, but he, like leaders in Washington, has to cope with a divided legislature. Tax-free development zones have been created in the disaster area, but they must overcome exaggerated fears of radiation.

Maybe nothing will ever be the same, in other words, but neither is everything transformed. Hard problems are still hard, and democratic politics are still slow-moving.