KIM DAE JUNG, freed from long imprisonment in South Korea, puts the right question. Is it better that the United States use its leverage quietly to obtain the release of well-known political figures like Mr. Kim? Or should this country exercise its influence more broadly in behalf of the general principles of human rights in the hope of ultimately benefiting more people--if, perhaps, less directly or dramatically? Mr. Kim, on arriving in Washington, expressed his gratitude to both President Reagan and Sen. Kennedy for their efforts to persuade the South Korean government to give him his freedom. But he declared himself in favor of the other policy, of attending to the general rules rather than the specific cases.

There he touches on one of the many dilemmas that this country constantly confronts in an alliance with a narrow and insecure military government like South Korea's. Mr. Kim's history is a particularly egregious example of South Korean transgression against international law, not to mention against the larger precepts of human rights. He was a one-man opposition in exile until, nine years ago, the South Korean Central Intelligence Agency kidnapped him from a Tokyo hotel and returned him by force to Seoul. The government eventually sentenced him to death for sedition, reversing itself two years ago after Mr. Reagan, who had not been expected to pressure the South Koreans on these matters, made commutation a condition of President Chun Doo Hwan's visit to Washington. Mr. Kim's arrival here last week is the result of further American intervention.

When Mr. Reagan came to power, Seoul was not the only capital that eagerly looked forward to a total abandonment of human rights concerns. Fortunately, those extravagant expectations have not been fulfilled. The Reagan administration has abandoned much of the policy approach of its predecessor. But it has also acknowledged a responsibility, as in the Kim case, to uphold American ideas of right in certain instances where it has seen both an obligation and an opportunity to achieve its purpose. It is a less ambitious policy than the Carter administration's, but it has its occasional victories too. Mr. Kim's release, while not signaling a general end to the repression in South Korea, is one of them.