HERE IS THE sequence: 1)Ambassador Jeane Kirkpatrick, visiting Chile, pronounces herself unaware of the precise status of the Orlando Letelier assassination case in the Chilean courts and calls for normalizing American-Chilean ties. 2)Two days later the Santiago regime summarily exiles four prominent opposition politicians, including Jaime Castillo Velasco, head of the human rights cause in Chile and the lawyer pressing the Letelier family's appeal before a military court. 3)A few weeks after that, the court rejects the appeal, leaving the now- lawyerless Letelier family unable to pursue the lone and final legal step available for gaining what vindication is possible in a police state.

Mrs. Kirkpatrick's statements affirming human rights and due process were big news in the Chilean press while she was there. But it insults her diplomatic acumen to suggest that it never occurred to her how the government might react to her remarks on the Chilean political exile who was murdered in Washington just five years ago. Obviously, the Chileans weighed her every word. They had other pretexts, all craven and arbitrary, to exile Mr. Castillo --a political adversary of Mr. Letelier's while Chile's democracy flourished, by the way--and the three others. But unquestionably the military government knew that a military court was bringing the Letelier case along, and it could see a window opening to get rid of it once and for all.

The episode offers a revealing glimpse of this administration's practice of the "quiet diplomacy" it has chosen in human rights. Ambassador Kirkpatrick's brief application of it in Santiago was followed close on by the sudden, brutal exile of four distinguished, courageous Chileans accused of no crime and by the sneaky maneuver in the Letelier case. Since it is inconceivable that Mrs. Kirkpatrick intended it to come out this way, the episode must be attributed to a stunning misjudgment that put her in a position to be so cynically exploited.

The ambassador has conveyed to Santiago, quietly, her profound personal regrets at what she takes to be the coincidence of her visit and the expulsions. It goes without saying, she says, that this administration does not condone any arbitrary legal process anywhere, including that which victimized Mr. Castillo. The trouble is that too much in this regard goes--too often--without saying by spokesmen for the administration.