THE MAULING the House has been administering to selected bits of the administration's foreign policy is a disturbing thing to behold. To be sure, the House did at least one major responsible deed by ending the Turkish arms embargo - a step that puts the Turks under an unavoidable obligation to make possible a fair settlement on Cyprus. But that was done in thoughtful response to a well-debated, carefully studied administration proposal - which, in turn, was based on a feeling for the situation in all its complexity that only a president and his diplomatic advisers can claim to have. In foreign aid, of which we have spoken separately, and on several substantive issues pertaining to particular countries, the House has acted with deplorable indifference to the real merits of the matters at hand.

We refer specifically to the readiness of the House of legislate on the floor without sifting proposals throught the committee system, which at least gives legislators the opportunity for study and debate and lets the executive branch make its case and muster its troops. The Turkish question went through the proper process, as did the Mideast arms package and, of course, the Panama Canal treaties; all ended in administration victories.

This week, however, policy amendments, hastily contrived and poorly constructed on the floor, carried on at least three issues. One, the amendment halting arms deliveries to Chile until it extradites three officials indicted in the murder of Orlando Letelier, was so patently wrongheaded that it was yanked back within hours. An alert Justice Department pointed out how absurd and provocative it was to punish Chile for not doing in one day what the law allows it two months to do.

Two other measures, however, do not lend themselves to remedy so easily. On Rhodesia, the House voted to lift trade restrictions by the end of the year if an elected government is installed. That is a blunt formulation that tramples on the subtleties that made the Senate's Rhodesia amendment difficult but bearable and even, under certain circumstances, usable by administration diplomats.

On Syria, congressmen suddenly cut off a year's worth of economic aid, ostensibly in reprisal for the assaults Syria has made on Christians in Lebanon in the course of trying to pacify that torn country. One does not have to approve of Syria's Lebanon policy to realize that an aid cutoff, on what is, after all, a secondary issue, may jeopardize that basis on which the United States is trying to win Syrian cooperation in the search for a Mideast settlement. Even more than on Rhodesia, the House moved on Syria without displaying the slightest sense of understanding of the overall play in that country's relations with the United States.

No better demonstration could be made that there cannot be 435 secretaries of state on Capitol Hill - or 535. The Senate at least has recognized - though perhaps fingers should be kept crossed - that it is both wise and fair to consult the administration even while challenging it.The House, however, is capable of going off half-cocked. Many members tend to slough off both committee discipline and party discipline, and to see no difference between doing so in domestic matters and in foreign affairs. (Republicans saved the administration on Turkey.) Congressional leadership no longer exists in a form that makes close executive liaison very productive on some of these issues. The Vietnam-born doctrine of prevailing congressional coresponsibility in foreign policy can become, at emotional moments, a license for irresponsibility.