Though President Carter doesn't talk much publicly about Iran anymore and the story is off the front page, the failure of the most important U.S. military mission in several years -- the effort to rescue the hostages -- has left troubling questions that aren't going away for many military officers.

These questions, raised privately in interviews with experienced officers on active duty who were not part of the small group that planned the top-secret mission, go well beyond the mechanical failures that left the rescue force with one helicopter less than what was needed to continue the mission.

Rather, the failure of a mission in which American prestige was on the line for all to see raises fundamental worries about whether the same civilian and military leaders who approved a plan based on such thin margins would also produce an easily flawed plan for dealing with a far graver military confrontation.

The questioners wonder about the quality of the current top military leadership, whether the White House was fully committed to seeing the operation through, and whether top military leaders are excessively prone to "saluting" in response to White House political needs. Also questioned is whether delicate military operations should be carried out by a combined four-services force rather than just one or two, and whether too many military and civilian commanders were cluttering the scene on this raid.

Because these questions are so serious, says one senior Army officer among about a dozen interviewed, "it is enormously important to be fair and know the facts. Maybe it was a good plan and just bad luck, though my belly tells me there may well have been a lot of screwing up, both military and civilian. So it is very important that the whole thing be laid out, that the civilian and military leadership learn from the facts."

What is needed, he says, is the kind of full-scale look inside a disaster such as was performed in the Kennedy administration after the CIA-run Bay of Pigs debacle.

The Pentagon is conducting its own "after-action" study of the mission. The study is being carried out by the joint staff of the chairman of the Joint Chiefs, Air Force Gen. David C. Jones, the same staff that planned the raid.

There is no indication that the Carter administration, which benefited politically from the rescue attempt even though it failed, is conducting the much broader kind of investigation. The White House has also declined to provide Congress with additional information on the aborted mission.

"I feel very strongly that there are lessons to be learned here . . . and that there are aspects of this operation that certainly should be subject to an impartial, blue-ribbon review," says Sen. Henry M. Jackson (D-Wash.), a powerful figure in defense matters on Capitol Hill.

This has nothing to do with the courageous men who actually carried out the raid, Jackson says, but rather with asking "was this operation wise and prudent. I think there is great concern within the professional services about the way this was handled."

If there were serious errors in decision-making and planning at the top, there is no indication that anybody has been penalized or even replaced, another aspect that troubles some officers.

"If you don't purge the failure," says another senior Army officer, "it will simply encourage other failures. If there is no penalty, it means you're not interested in success. Would you want the same group to plan the next operation?" he asks. "Would you have confidence in them?"

"In any other country, East or West," adds another Army officer, "heads would have rolled. People would have resigned. We are too forgiving here."

"Somebody ought to be paying some kind of price," an Air Force colonel declares. But in his view, "the biggest problem we see is that we have a military leadership today that is spring-loaded to say 'yes sir' and an administration that tries to run the military on a shoestring. That mission was run on a shoestring."

Among officers worried that the military may have said yes to a "mission improbable" to help get the hostage issue off the president's back and allow him to end his Rose Garden strategy, the private expressions of concern are mostly directed, fairly or not, at Gen. Jones.

Says a fellow Air Force officer: "Jones is perceived as a political general who is, very, very responsive to the president, who always rolls with his boss."

Jones was just renominated by Carter to a second two-year term as chairman of the Joint Chiefs of Staff. Air Force Lt. Gen. Philip Gast, who was a special assistant to Jones for the rescue operation, was named as director of the joint staff after the rescue mission.

While military officers express different views on some points, such as whether people ought to resign or to be fired, there is virtual unanimity that the biggest flaw lay in cutting too close on the number of helicopters and other equipment on such a tough mission.

"Once you give the order, commit the operation and you've got the reputation of the United States on the line, it's got to go, got to be completed, got to be a success and you've got to have the resources to do it," says an Army colonel.

From what has been learned unofficially about the raid, there were numerous points along the planned rescue route in which the mission could have been aborted, or called off.

While some of these locations were good safety valves, many officers felt the idea of having them all along the line reflected too much hesitancy about the raid to begin with.

A similar point was raised recently by retired Army general Maxwell Taylor, a former chairman of the joint chiefs who also chaired the special group set up by President Kennedy to study the Bay of Pigs failure.

"The fail-safe procedure used in Iran has much to recommend it," Taylor wrote. "However, it also raises the question of the possible effect on leaders when escape hatches are so readily accessible. In the course of history, the successful commander has often been the kind of man who deliberately burns his bridges behind him to prevent thought of anything but victory."

Taylor expressed hope that at some point President Carter would also conduct a searching post-mortem on the raid.

"If he did so," Taylor wrote, "I suspect that the major lesson taught by the failure of the rescue mission would be essentially the same as in the Bay of Pigs. In both cases, the decision to act was not accompanied by a determination to succeed, followed by an allocation of resources more than enough to assure success. In both cases our government tried to do too much with too little and with insufficient regard for the eternal verities of Murphy's Law," which says that if anything can go wrong, it will.