ONE OTHER MEASURE suggests itself: it is tempting -- just so tempting -- to let the Iranian students have it, all 50,000 of them, in retaliation for the brutal treatment of American diplomatic personel in Tehran. We understand the impulse. In some respects we share it. The sight of mobs of these students tearing up the place -- this place, not Iran -- is enraging, and there is clearly psychic relief to be had from reacting to them as a group. "Get the hell out" -- that is the message you long to deliver to these demonstrating students and through them, to their incivil government. It is a strong temptation -- and one that must be strongly resisted.

This has come up before. Last January, when a bunch of Iranian student-louts staged a bloody, destructive demonstration in California, storming the residence of the shah's sister, some setting fires and inflicting injuries, the same emotions were triggered and the same demands to get rid of the whole lot expressed. What tempered the response then was the Justice Department's insistence on abiding by the inconvenient provisions of the law, those complicating and blessed safeguards against the arbitrary use of official power that define the difference between the United States and, let us say, Iran.

It is hard just to up and kick people out of this country -- even people here on temporary visas who have "violated their status," as the broad category for offenses is known. Hearings and appeals and the rest inhibit the government from doing anything much in a summary way. Given the arbitrary and overbearing misuse of authority that immigration officers in the past have engaged in, these protections themselves are well worth protecting. And at the moment they need it.

Does the administration appreciate this need? Not so you'd notice at the moment. Students other than Iranians are in violation of status all over the country. But it is, evidently, only the Iranians who are being rounded up for questioning -- whether they have broken a law or not. This ethnic approach (no Syrians, Israelis, or Mexicans need reply) is in itself offensive and redolent of bad days gone by. So too is the Justice Department's statement that this is being done "in response to the international crisis created by the unlawful detainment of American citizens in the American Embassy in Tehran." Does that mean in reprisal? What does it mean?

Finally there are the reports that Immigration officers have been instructed to ask of the rounded-up Iranian students whether they have participated in demonstrations here and whether they belong to organizations that are pro or con this government or the government or the government of Iran. If this is true, it suggests that to the ethnic standard for invoking the terms of the law, the government is adding a test of political views. We repeat: our own thoughts upon looking at some of these Iranian demonstrators are nothing pretty. But it was precisely to guard against the self-damaging excesses that can be the product of such emotions that this country's constitutional protections were fashioned. It will be self-defeating and disgracing if, in order to fight a mob, this country lets itself behave as one.