IT IS a sad measure of the general American frustration in the Iran crisis that it is not the immediate freedom but the prospective transfer of the hostages, from the terrorists' to the government's hands, that is being so eagerly awaited: for some time, anyway, the Americans would remain prisoners. It is an even sadder measure that for this step, which is not yet assured, the United States is paying quite a price. That price is a promise to "desist from any propaganda, agitation and machinations" until Iran's new parliament -- which has not yet been elected, which has never met, and which may have its own ideas on the matter -- meets some time hence.

Why would the administration accept the onerous conditions of a gag, a suspension of its recently threatened sanctions and a foreign veto on its policy? The immediate answer is, of course, that communications have been going back and forth that have led President Carter to believe that Iranian President Bani-Sadr, who is conceivably ready to liquidate the crisis brought on by the seizure of the American hostages, has a chance of bringing this about.

The larger answer is that given his early and unwavering decision not to use force, President Carter has had no alternative but to involve himself in the Iranian political process. The economic and diplomatic levers he has sought to use, from time to time, have either not been pulled effectively enough or simply are not powerful enough to pry the hostages loose on their own. The Iranians, thus freed of serious costs, have continued to press their demand for an official accounting for American policy in the past. Mr. Carter evidently moved toward satisfying this demand in one or more recent messages that some Iranians found conciliatory -- a characterization that Mr. Carter has been at pains to deny. Since the accounting may be his best remaining card, and one that it will be extremely distasteful to play, he is proceeding warily.

Whether the diplomacy between Washington and Tehran puts the hostages in the Iranian government's hands may be known soon. Mr. Bani-Sadr's complaint last night that President Carter's no-propaganda declaration had not been sufficiently "official" underlines the difficulties. The administration's whole exercise in no-hands diplomacy is in the balance. If the transfer takes place, it will be taken as a step forward -- though that is a judgment that only events can validate -- and other steps pointing to the hostages' release can be essayed. If the 50 Americans remain in the clutches of their current captors, their agony is prolonged and Mr. Carter will have lost virtually all claim to be presiding over any kind of policy on Iran.