TOKYO -- If you want to understand why America is losing the economic war with Japan, pay a visit to a Japanese bookstore. One of the hot new books this season is a "manga" (comic book) guide to superconducters. The protagonists are young Salarymen, determined to help their company win the race to exploit the new technology for transmitting electricity. The characters do not develop beyond caricature, but the book succeeds in its mission: To explain superconductivity to the masses.

The comic book isn't the only example of Japan's fascination with superconductivity. A few months ago, two (non-manga) books on superconductors were on the Japanese best-seller list, and a dozen books on the subject were prominently displayed in one large bookstore in Tokyo. In America, in contrast, I have yet to come across a single book on superconductors. This is a technology, mind you, which has become "the test of whether the United States has a technological future," according to Frank Press, president of the National Academy of Sciences.

The Sanseido bookstore in the heart of Tokyo is a convenient place to gauge the mood and the dynamics of today's Japan.It is truly a tower of words: six floors of books, totalling 1.2 million volumes and about 300,000 different titles. The place also stocks over 2500 different magazines. The foreign language book section alone is bigger than many of the bookstores in Washington.

The store is full of surprises. An American visitor hears a shrill voice repeating endlessly the phrase: "Yeah, I think I'll buy them an anniversary present." The voice comes from a Sony "repeater machine," which Japanese use to teach themselves English. Nearby lies a book in Japanese with the improbable title: "You, Too, Can Read Porn in English With Only Your Middle School English." "Can't stop if you start!" it promises. These items are examples of the Japanese obsession with learning a foreign language -- and finding a bridge to the rest of the world.

"Success!" says a large sign on the sixth floor of the bookstore, hung above stacks of college-entrance guides bearing the names of famous Japanese colleges. This display attracts a small crowd of success-minded students. A small torii (the red gateway to a Shinto temple where students and their parents often go to pray for success before a college entrance exam) stands in its midst, calling to the heavens if sheer effort is not enough. The student anxiety is understandable, since 344,000 applicants who wanted to enter college last spring couldn't get in, according to Asahi Shimbun.

On nearby shelves, "stress management" cards are sold. (If you hold the card firmly in your hand and the indicator turns green, you are relatively relaxed; red is a warning sign, and black indicates deep stress.) Here, they also sell "relaxation tapes": a soothing voice urged the listener to stop studying for a while, "rotate your neck s-l-o-w-l-y . . . stretch your arms . . . breathe d-e-e-p-ly."

The Japanese may be the greatest readers on earth. For each of the past seven years, they have consumed over a billion books and magazines. In 1985, they purchased over 48 million newspapers a day. Less than one percent of their 121 million people are illiterate. Last year, according to the Japanese Research Center on Publishing, they printed 4.01 billion magazines and 1.45 billion books.

The manga craze is the latest example of Japan's logophilia. There are over 150 different comic magazines, some with whopping circulation figures: The weekly Shonen Jump magazines for juveniles, a thick publication (almost 300 pages) filled rim to rim with a variety of cartoon series with its characteristic wham-bang-slash-zap-wow dialogue, sells over 4 million copies each week.

"I read the "Manga History of Japan" {in 19 volumes} to supplement my college entrance exam studies," said Shinichi Igeta, a senior in high school. "It's easier to remember plots and faces in the manga version than in the ordinary history textbooks," the student from Yokohama said.

Cookbooks, biographies, books on science -- almost any genre or subject matter has been converted into manga form. When the Nakasone government tried to pass legislation for a new new sales tax earlier this year, they came up with a booklet to sell their programs complete with manga illustrations; the opposition parties resorted to the same tactics. Nomura Securities recently published a manga guide to stocks and bonds aimed primarily at female office workers and housewives (who traditionally maintain control over the family's purse strings).

"The Manga Introduction to Japanese Economics," which has been on the best-seller list for several months, has already sold over a million copies in hardcover, and was quickly followed by volumes II and III. The book was published by the prestigious Nihon Keizai Shimbun, the Japanese counterpart to the Wall Street Journal (but with a bigger circulation).

Alook at the current best-seller list will indicate who is buying the bulk of books published in Japan. Older businessmen and young salaried workers were snatching up copies of "Japan Is in Danger," "What Must One Do to Avoid Loss?" "The Japan-U.S. Economic Friction." David Halberstam's "The Reckoning," about the fall of the American car industry and the rise of Japan's, was also on the list. It was televised as a documentary in four one-hour segments by NHK, Japan's national television network earlier this year. "What They Really Teach You at the Harvard Business School," by Francis J. and Heather M. Kelly, was another American book on the list.

Sensational books sell, the more outrageous the better, it seems. A book called "If You Worry About Judea, the World Will Never Come Into View," was on the best-seller list. It's a welcome rebuttal to an earlier book by Masami Uno, "Understand Judea and the World Will Come Into View" -- a blatantly anti-Semitic book blaming much of Japan's economic woes on a world-wide Jewish conspiracy.

The bookstore stocks an amazing number of books that have been translated from English into Japanese. These range from the Random House Dictionary to the Encyclopedia Britannica, from the novels and short stories of Stephen King and Raymond Carver. After over a century of acquiring information from abroad, the flow has become torrential. Besides Cable News Network's round-the-clock news, ABC and BBC television news programs are now beamed directly to Japan via satellite. The flow of information from the United States into Japan is probably as much as 10 to 1 in Japan's favor.

Japanese know that only a trickle of information about their country reaches the United States, due mostly to the barrier posed by the Japanese language. Even among American journalists who cover Japan, only an exceptional few can read and speak Japanese. This imbalance has given rise to a view currently expressed in books and magazines: that it is no longer Japan but the United States which has increasingly lost touch with the outside world.

"Japan and America," a book written by the staff of the Asahi Shimbun newspaper, contains an estimate that there are less than 400 Americans in the entire United States who are capable of translating technical information from Japanese into English, that only about 10 each year will reach the level of proficiency in Japanese to be able to translate such information. And in a recent article in "The 21," ("the new data magazine in which you can see today's and tomorrow's civilization"), a writer named Kew Eikan asks: "What will happen if one day the Japanese could conduct all of its transactions in its own language? Will it, like the Americans, be enclosed within its own linguistic barriers and not know what is happening outside its walls?"

Magazines are a special case of Japan's reading-mania. There were over 31,000 different kinds of magazines published in 1985, of which about 4000 were for mass distribution. At Sanseido, as at any bookstore in Japan, more customers flock around the magazine sections than anywhere else.

There are Japanese-language editions of Esquire, Newsweek, Scientific American, Elle, Playboy, Penthouse and many other American and European publications. The men's magazines have been adapted to Japanese tastes using Japanese models and articles written expressly for or in Japanese. Like the Japanese Barbie dolls (with shorter legs, smaller breasts and a cartoon-like pubescent look) the alterations are made to fit the local image. The original English language versions of Playboy and Penthouse also can be found in Sanseido's -- with their centerfolds retouched. In Japan, it's illegal to show pubic hair!).

The trendy Japanese magazines for young men -- Popeye, Hot Dog, and Big Tomorrow -- aren't much different from their American counterparts. They are essentially guides to leisure -- where to surf, where the trendiest restaurants and clothing stores can be found, which "love hotels" (assignation places rented by the hour) to take your date to. Such frivolous magazines are perhaps a reaction to the years of "examination hell" that they have lived through.

Magazines containing housing information sell very well, reflecting the current insanity of ever-rising land prices (some prime sections of land in Tokyo have gone up over 70 percent in one year alone) and the shortage of available rental property in the Tokyo area.

Magazine advertisements tell another story, of growing affluence. Fully-automated bread-making machines (all you need to do is pour in a prepared mixture at night, set the timer, and the next morning it will be ready at the precise time you want, sufficiently cooled), a compact disc player which also plays movies on laser discs, three-dimensional television, self-heating canned-sake, are some of the latest hot sellers among the gadget-loving Japanese.

The buzzword in many mainstream magazines these days is kokusai-ka, or "internationalization," which is often used with another buzzword -- keizai-masatsu, or "economic friction." A theme of many of these articles is that recent Japanese-American tensions aren't due simply to economic forces such as the imbalance of trade or the rise of the yen, but to Japan's inability to communicate its position to the rest of the world. Government officials are unable to effectively present Japan's side of various trade issues abroad. Businessmen are unable to be at ease with foreigners and their cultures.

Kenichi Ohmae, the ubiquitous author, commentator and executive of MacKenzie & Co., wrote in the September issue of Bungei Shunju that customs, the structure of government, trade practices -- the very way Japanese think -- should be reshaped for Japan to become a great nation. The goal , he suggested, should be to accomplish this by 1995 -- the 50th anniversary of the end of World War II.

Kunio Francis Tanabe is an assistant editor of The Post's Book World section.