THE GENEVA MEETING on Indochina refugees opening today offers Vietnam perhaps its last chance for years to solicit halfway good relations with the rest of the world. This statement is extreme but not exaggerated. Vietnam, by expelling hundreds of thousands of its citizens (most of them ethnic Chinese), has earned as rare measure of loathing. Earlier, the Communist government in Hanoi, by its harsh treatment of so many of its own citizens and by its takeover of Cambodia, had sisipated much of the peculiar standing it had at the time of its victory over the United States in 1975. Its refugee policy since has pretty much completed the devastation of its international reputation, alienating it from its near neighbors, exposing it to the twin perils of further hostility from Peking and deepening dependence on Moscow, and cutting it off from the Western sources of aid and patronage on which it once had reason to rely.

Even an enlightened performance at Geneva will not spare the Vietnamese all of these consequences of its own conduct. Heavy damage has already been done by an official policy that has cost uncounted lives among refugees lost at sea and that has piled up a third of a million other refugees in wretched temporary asylum elsewhere in Southeast Asia. Vietnam, however, may still have a certain room left for bargaining. It can try to show that it now means to start abiding by elementary standards of international decency: that it will stop forcing and winking at (both apply) the departures of tens of thousands of desparate, panicked people monthly, and that it will exert itself to put into effect the United Nations-arranged procedures for orderly departure that it claims to be ready to use. With such a showing, immediate and clear-cut, Haoi will at least be in a position to ask the international community to reveiw its sentence to pariah status. Without it, diplomatic "parole" is out of the question.

Some 60 other nations, with the United States in the lead and the Soviet Union (Vietnam's patron) not daring to show its face, will be at Geneva. The meeting will be a kind or resettlement telethon in which pledges of resettlement homes and funds will be made to clear out the camps in Thailand, Malaysia and Indonesia. No permanent relief can be assured the countries that have accepted Vietnam's human jetsam, however, if Vietnam cannot be brought to understand its own future stake in slowing down the flow to a rate consistent with the safety and welfare of the refugees and with the absorptive capacity of the rest of the world.