The Conquest of America : RISING SUN, <i> By Michael Crichton (Knopf: $22; 355 pp.)</i>

What’s all the fuss about? Last week, Michael Crichton’s “Rising Sun” was rushed to publication a month earlier than previously announced, breathless publisher Alred A. Knopf citing “extraordinary timeliness with regard to U.S.-Japan relations.” (Translation: Somebody broke the embargo.)

* On the day it was officially published, the novel debuted at the pinnacle of the best-seller list, where it is expected to stick like rice to raw tuna.

* “Rising Sun” is a main selection of the Book-of-the-Month Club, available in large type and talking book.

* Pulling out their own stops, Kirkus Reviews said of their advance copy, “The Yellow Menace returns. . . .” (Not that we expect you to remember, but it’s Peril , guys, Yellow Peril . Dennis is the menace.)

* On a more somber note, at least one distinguished journal likened “Rising Sun” to “Uncle Tom’s Cabin”!

Not quite.

What it is is a curious hybrid of mystery and polemic, four parts portent to one part whodunit. It is a strange forum for a thesis: a heartfelt, articulate but sometimes strident warning. The Japanese, says Crichton, are taking over America, by means fair and foul--and with the acquiescence of the Americans, too dumb to realize what’s going down.

The carryall for this baggage--the mystery part--is quite delicious. A concupiscent blonde (we assume she’s a blonde; they always are) is found dead on the executive-office floor of the Nakamoto Tower, Figueroa and 7th. It is opening night for the tower, at 97 stories Los Angeles’ highest; partying on the floor below is the cream of American society: Tom Cruise, assorted Kennedys, Madonna . . .

The Japanese, who want their own private inquiry, have impeded the LAPD crime-scene investigation, and liaison detective Pete Smith is called in. So is Capt. John Connor, who has lived at length in Japan, is in tune with its nuances, and is a royal pain. (Throughout, he insists on calling the stolid Smith kohai , sort of the Japanese equivalent of junior .)

As a sleuth, though, Connor is a kimono Columbo. He finds clues in such arcana as horseradish-covered peanuts and the fact that there were no reading glasses in the home of a suspect; he also seems to be the only detective in the loutish Western world to know by now that when a body is “charred beyond recognition” it is never who you think it is. Was.

The detective story soon clouds over with evidence that there is a massive cover-up afoot, orchestrated by Japanese business interests; indeed, the plot turns on the humbling proposition that the Japanese are far more clever than we in doctoring the security videotapes that recorded the Nakamoto affair.

It is here--in the videotape clues--that we begin to appreciate how deeply the Japanese have infiltrated our economic infrastructure. The LAPD cannot have the tapes analyzed because the Japanese own all the labs. They also own L.A. and are swilling down Orange County. They have staked claims to the entire state of Montana, half of our research scientists and most of the Congress, and would own the President, too, if they hadn’t botched the job. (No, that’s not in the book, but remember that banquet . . . ) They even own the L.A. Times, and mister, that hurts.

What has all this infiltration got to do with the dead blonde?

In a way, everything, since her death is the fulcrum of an elaborate plot to pressure Congress into approving sale to Japan of yet another vital computer-chip company (“MicroCon,” a doppelganger for Fairchild Semiconductor).

Perhaps nothing, too, since the chicanery serves primarily as a bully pulpit for Crichton’s impeachment of the Japanese. The Americans of “Rising Sun”--mainly LAPD types, with a smattering of soused Senators--are generally trustworthy, loyal, helpful, friendly . . . if slothful, naive and profane. The Japanese, manipulating behind the scenes, are devious, arrogant, ruthless, racist . . . if hard-working and unfailingly polite.

Narrative flow is repeatedly, annoyingly interrupted by 10, 20, 30 pages of pedantic peroration on Japanese business practices--no less irritating for their authenticity:

* TV: “After World War II America was the world’s leading manufacturer of television.” Twenty-seven U.S. companies sold their product worldwide--except in Japan, which insisted we first license our technology to Japanese companies. The U.S. firms complied. By 1976, 100% of American black-and-white TV sets were Japanese; same story with color-TVs: Only one American firm--Zenith--still makes them.

* Cameras: Japanese tourists buy Japanese cameras in America, where, despite import duties and distribution costs, they’re cheaper. In Japan, U.S.-made cameras are marked up 70%; they don’t sell.

* Cars: “In the old days, if a Japanese bought an American car, he got audited by the government. So pretty soon, nobody bought an American car. The officials shrug: What can they do? Their market is open: they can’t help it if nobody buys an American car.”

* Skis: No U.S. imports. Why? The Japanese said their snow was “wetter.”

* Beef: American beef rotted on Japanese docks. Hard-hit, Montana ranchers sold their spreads to the Japanese, who hired them at handsome salaries to run the operations. Japan now buys “American” beef--from Japanese-owned ranches.

It’s done by mirrors, of course, and by dumping and price-fixing and bribes and customs fraud--just about anything to get a foot in the door, then a leg, then total control, all the while conspiring to keep U.S. products out of Japan. And underscoring each maneuver there is rampant racism:

“The Japanese are the most racist people on earth,” says Connor (and he’s a friend ). “(They) think everybody who is not Japanese is a barbarian. They mean it, literally: barbarian . Stinking, vulgar, stupid. They’re polite about it, because they know you can’t help the misfortune of not being born Japanese, But they still think it.”

And with the racism comes contempt. Twisting the knife, Crichton has a character recall a “joke” told by former Prime Minister Takeshita Noboru “about visiting American sailors on a Navy ship. He said America is now so poor, the Navy boys cannot afford to come ashore . . . He said they could only remain on their ship and give each other AIDS. Big joke in Japan.”

The mystery? Lost back there in the squad car, where Connor and Smith, en route to a bust, continue to debate the finer points of corporate takeovers.

There are lessons to be learned from “Rising Sun” but maybe they’re the wrong ones. Maybe it would be better to stop riding a scapegoat and start carrying our own load.

Meanwhile, a nagging question: If the Japanese are so damn clever, why are they financing our deficit?

Just asking.