TONGSUN PARK, the South Korean businessman whose idea of friendship Washington-style included handing out cash in envelopes to congressmen several years ago, finally has achieved the status of the Americans he so often emulated: He owes the IRS.

The U.S. Tax Court ruled Aug. 10 that Park was a resident of the United States for tax purposes from 1972 to 1975. At the time, he was collecting millions of dollars in commissions from the sale of U.S. rice to Korea without paying taxes, and dishing out tens of thousands of dollars in gifts to his congressional friends.

Another Tax Court proceeding will determine how much he must pay of the $5.5 million the IRS is after. His attorney, former IRS Commissioner Sheldon S. Cohen, said the government already has seized Park possessions in Washington worth nearly $2 million.

The thought of the IRS winning over Park after all these years is comforting, even poetic, some might say, given his charmed life in the scandal, his affection for big bucks, and his proclivity for American ways.

Until now, the 47-year-old millionaire has escaped from the scandal practically untouched. He was indicted on bribery and conspiracy charges in 1977 after an FBI investigation of South Korean attempts to buy influence for continued American aid to the Seoul government. But he fled the country and returned only after an agreement in which he traded his testimony about payoffs for dismissal of the charges against him.

Park still returns to Washington periodically and moves in the same social circles he used to cultivate officials in the early 1970s. On June 15, for example, he hosted a dinner at the George Town Club he helped found with Korean CIA money.

Guests were willing to partake of Park's hospitality but were reluctant to acknowledge to a reporter that they attended. While his acquaintances were looking for a place to hide, he said: "I would never abandon Washington. Washington is a marvelous city for someone like me. Where else could a foreigner, an outsider like myself, do the things I was able to do?"

When he first testified about his gift-giving to the House ethics committee in April 1978, he described his activitives as "the American success story on a small scale."

Small indeed. The 78-page Tax Court ruling summarizes his life and times in Washington, from his string of expensive homes, cars, clubs and "Green Book" social acceptance to the millions of dollars he stashed in offshore bank accounts in an attempt to avoid taxes. His extensive business and social and political ties in America were not those of a "mere transient or sojourner," the court said.

Its findings mention his succession of expensive homes here and in London, Seoul and the Dominican Republic -- one equipped with a $20,000 sound system -- his Lincoln and Jaguar with their "TSP 1" and "TSP 2" license plates, the $1 million he shipped home to the Korean school foundation he runs, the $20,000-a-year gifts he made to each of three separate symphony orchestras in Korea, the $800,000 estate he bought there and shares with his mother.

The ruling even noted that he taught Sunday school and played the violin in the Tacoma Symphony in 1955 while he attended the College of Puget Sound. "There was so much the press never knew about me," he told a reporter inquiring about his June party.

Instead of violins and Sunday school, the press and Justice Department prosecutors concentrated on the way Park used his flow of Korean government-sanctioned rice money to entertain and impress Washington politicians and businessmen.

Former Attorney General Benjamin R. Civiletti, who headed the department's criminal division during the scandal, once expressed surprise at how easy it was for Park to win the hearts and minds of the powerful in this city.

For years, no one seemed to wonder about the motives of the smiling young man who picked up the tab for elaborate dinners for congressional leaders, expensive food, wine and gifts included. Apparently few also wondered why he began to give members of Congress thousands of dollars in cash campaign contributions.

Rep. Millicent Fenwick (D-N.J.), a member of the House Ethics Committee, which disciplined a handful of members for their dealings with Park, said, "We have a system that invites it."

Park was extremely generous to a handful of politicians. Rep. Otto E. Passman, chairman of a powerful appropriations subcommittee, was indicted for taking more than $213,000 from Park, but was acquitted after the trial was transferred back to Louisiana. Passman is now retired in Monroe, living on his congressional pension estimated to be more than $30,000 a year.

Rep. Richard T. Hanna (D-Calif.), the only member to go to prison for his part in the affair, allegedly accepted almost as much, although his attorney recalls it actually was only $78,000. Hanna is now living in Fayetteville, Ark.

Tongsun Park's white-envelope campaign and the government's success in fighting it pales now in comparison to the haul the FBI made in its recent Abscam cases.

In that investigation another foreigner -- well, a forged foreigner, an undercover agent posing as an Arab sheik -- discussed cash in envelopes with crooked politicians before hidden cameras in airport motel rooms.

There were no videotape witnesses to Park's handouts. But it also seems certain that Park would have found that operation unsavory, lacking the class of his "Green Book," George Town Club bribery.

His "American success story" was uniquely a Washington story, peopled with the gullible and the greedy. And now because "he was not a stranger in an alien land," the court said, he must join the ranks of the rest of us.

He escaped prison, but not the tax man.