Time and again, Americans are told to look to Japan as a warning of what the country might become if the right path is not followed, although there is intense disagreement about what that path might be. Here, for instance, is how the CNN analyst David Gergen has described Japan: “It’s now a very demoralized country and it has really been set back.”

But that presentation of Japan is a myth. By many measures, the Japanese economy has done very well during the so-called lost decades, which started with a stock market crash in January 1990. By some of the most important measures, it has done a lot better than the United States.

Japan has succeeded in delivering an increasingly affluent lifestyle to its people despite the financial crash. In the fullness of time, it is likely that this era will be viewed as an outstanding success story.

How can the reality and the image be so different? And what can the United States learn from Japan’s experience?

It is true that Japanese housing prices have never returned to the ludicrous highs they briefly touched in the wild final stage of the boom. Neither has the Tokyo stock market.

But the strength of Japan’s economy and its people is evident in many ways. There are a number of facts and figures that don’t quite square with Japan’s image as the laughingstock of the business pages:

• Japan’s average life expectancy at birth grew by 3.1 years — to 83 years from 78.8 years — between 1989 and 2009. This means the Japanese now typically live 4.8 years longer than Americans. The progress, moreover, was achieved in spite of, rather than because of, diet. The Japanese people are eating more Western food than ever. The key driver has been better health care.

• Japan has made remarkable strides in Internet infrastructure. Although as late as the mid-1990s it was ridiculed as lagging, it has now turned the tables. In a recent survey by Akamai Technologies, of the 50 cities in the world with the fastest Internet service, 38 were in Japan, compared to only 3 in the United States.

• Measured from the end of 1989, the yen has risen 87 percent against the U.S. dollar and 94 percent against the British pound. It has even risen against that traditional icon of monetary rectitude, the Swiss franc.

• The unemployment rate is 4.2 percent, about half of that in the United States.

• According to skyscraperpage.com, a Web site that tracks major buildings around the world, 81 high-rise buildings taller than 500 feet have been constructed in Tokyo since the “lost decades” began. That compares with 64 in New York, 48 in Chicago, and seven in Los Angeles.

• Japan’s current account surplus — the widest measure of its trade — totaled $196 billion in 2010, up more than threefold since 1989. By comparison, America’s current account deficit ballooned to $471 billion from $99 billion in that time. Although in the 1990s the conventional wisdom was that as a result of China’s rise Japan would be a major loser and the United States a major winner, it has not turned out that way. Japan has increased its exports to China more than 14-fold since 1989 and Chinese-Japanese bilateral trade remains in broad balance.

As longtime Japan watchers like Ivan P. Hall and Clyde V. Prestowitz Jr. point out, the fallacy of the “lost decades” story is apparent to American visitors the moment they set foot in the country. Typically starting their journeys at such potent symbols of American infrastructural decay as Kennedy or Dulles airports, they land at Japanese airports that have been extensively expanded and modernized in recent years.

William J. Holstein, a prominent Japan watcher since the early 1980s, recently visited the country for the first time in some years. “There’s a dramatic gap between what one reads in the United States and what one sees on the ground in Japan,” he said. “The Japanese are dressed better than Americans. They have the latest cars, including Porsches, Audis, Mercedes-Benzes and all the finest models. I have never seen so many spoiled pets. And the physical infrastructure of the country keeps improving and evolving.”