DESPITE WHAT Americans believe they know, the seizure and abuse of diplomats as well as private citizens is far from unprecedented; it has been a rather regular occurrance during historical periods of turbulence and revolution. The victims have been American, Russian, British and a variety of other nationalities in a dismayingly long tradition.

Why then did the seizure, confinement and eventual release of 66, later 52, American hostages in Tehran strike this country with thunderclap force, becoming a crisis of an overwhelming and all-absorbing nature? Why did the Carter administration concentrate on this beyond all else in a dangerous world, to the extent that more than 100 meetings of the National Security Council or its crisis coordinating committee within the first six months? And why are Americans likely to remember this travail and release on the scale of great events, such as the beginning or ending of a full-scale war or the death of a president?

Many factors, foreign and domestic, were involved, but two reasons stand out beyond all others:

First, the plight of the hostages in Iran seemed to sum up and symbolize a sense of vulnerability and ineffectiveness in relation to the rest of the world which had been growing in this country since the fall of Saigon in 1975, and was rooted in the more distant past.

The nation which had emerged from World War II far and away the most powerful as well as the most admired was increasingly frustratedd and buffeted by outside forces beyond its control. National adjustment to a more modest role is often painful. The taking of a U.S. embassy, a symbolic seat of nationhood, seemed to seize the nation as well as its diplimatic and military personnel by the throat.

Second, and closely related to the first, is a new fact of our age with profound significance: the ability of human beings with the right equipment to bounce sounds and images off satellities in space and transmit them widely and instantly to millions of others across the globe. In this wired world in which we live, fragments of experience from afar can be hurled into the national consciousness with incredible velocity and impact. The effect is all the greater when the event is not only dramatic and symbolic but also intensely personal, involving the suspended fate of identifiable people.

The world stage was not lit nor the cameras rolling in 1796, when the United States signed an early day "agreement of Algiers" and paid $992,463.25 for the ransom of the passengers and crew of two American ships which had been seized and held by the dey of Algiers for 11 years. The payment of ransom by nations was commonplace in those days.

Nor was there much commotion beyond a limited circle in 1829 when a mob of several thousand Persians, egged on by mullahs, saced the Russian legation in Tehran, slaughtered nearly all 38 of Moscow's diplomatic personnel and dragged the body of the Russian envoy through the streets. The Russian offense, in Persian eyes, was to give asylum to two girls and a eunuch from the harem of the shah and his family. There was no retribution.

In china in 1948-49, following the communist victory in the civil war, authorities in Mukden penned up the 10 diplimatic personnel of the U.S. consulate plus their Chinese staff and a hapless German who had stopped by to visit the library. This confinement under rigorous conditions lasted for more than a year, six months of this period without any contact with the outside world. Nobody remembers this now.

Another Chinese episode during the Maoist Cultural Revolution was perhaps the closest contemporary parallel to the recent events in Tehran. In 1967 and British chancery in Peking was sacked and burned by quasi-official Red Guards, several British diplomats were beaten by a mob and subsequently all British diplomats were detained in their compound for four months by government order. At about the same time the Soviet embassy in Peking was repeatedly attacked and harassed, with the Russians counting some 80 government-backed "provocations" within 1967 against their diplomatic mission or personnel, and another 120 "spontaneous outrages."

From 1968 to 1979 the State Department counted 273 terorist incidents of all sorts against U.S. diplomatic interests overseas. The Rand Corporation's most recent listing of international terrorist acts against all countries since 1968 runs to 1,400 incidents. Nearly 100 diplomats have been assassinated or kidnaped in that period.

A Rand report issued a few days ago said terrorists or other militants have seized embassy facilities of various countries on 43 occasions since 1971, with five of these incidents involving U.S. embassies. "Seizing embassies became a common form of protest and coercion in the 1970s," according the Brian M. Jenkins of Rand.

The takeover of the U.S. embassy in Tehran, in this light, involved the seizure of the largest number of diplomatic personnel, and for the longest time, of any single contemporary incident. This are distinctions which made it noteworty, as did the ambiguous quasi-governmental nature of the hostage-keeping, but in themselves they hardly explain why this became the "Iran crisis" which shook the United States and involved most of the world.

In Washington's inner circle as well as on the outside, the events of Nov. 4, 1979, were very personal. The high officials along with the rest of the country saw the television pictures of screaming crowds waving their fists outside the embassy while the blind-folded hostages were paraded inside. "I know this was going to be overwhelming," said Capt. Gary Sick, the NSC staff aide on Iranian matters. "In the White House situation room within the first 24 hours I made a commitment, almost like taking vows, that until those people were out that would be the total priority in my life. We discussed it at the dinner table, and my family understood. From then on, seven days a week became totally routine and 16-hour days were normal."

When all the elements of the United States government were mobilized, due to the intense personal interest and commitment of President Carter and the topmost layer, Sick was receiving 1,000 pages of cables, memoranda and reports per day across his desk, more than he had time even to skim between White House meetings.

The president himself, as disappontment piled upon disappointment and the Soviet invasion of Afghanistan added to the air of crisis, seemed a changed man to those around him. "This hostage thing is preying on his mind. It's almost like it haunts him," said Robert Strauss, his campaign manager, three months in the long ordeal.

The overwhelming, almost single-minded governmental cocentration on on the event both arose from and intensified the concentration of the press and public. "The emotion level of the American people, the pain, anger and frustration that they felt and they we felt, was not something the administration had control over," recalled NSC aide Sick. "Anybody who suggested in those early months that this should be played down would have been laughed at. No public figure could stick his nose out of his office without being swamped in the national feeling. The immediacy of it penetrated the consciousness and overwhelmed us."

The question persists: Why was this so? No armies were marching, as they were in Afghanistan.There was a physical threat to several dozen of the 225 million American, but no physical threat to the United States.Moreover, it became apparent after a few weeks to nearly everyone, as passion in the United States intersected and interacted with passion in Iran, that a quick resolution was unlikely.

Part of the reason was the raw nerve touched upon by Jeff Gralnick, executive producer of ABC Televison's "World News Tonight" program, who hit upon the gripping title of "America Held Hostage" for a series of late night specials on Iran. Many Americans completely identified their country's fate with that of the hostages. For some, the identification was os intense and personal, they told members of hostage families, that they were unable to sleep well as they tossed at night worrying about what would happen next.

It is too simple to single out instant international mass communications, via satellite and television, as the only reason for the puzzling disparity between the scale of the event and the scale of its repercussions. Yet this fact, which made the daily drama part of the life of nearly every American from president to private citizen, separates the "hostage crisis" in Iran from all that went before. If Vietnam was the nation's first television war, the ordeal of the Tehran embassy was the first televised international crisis.

It has been suggested by many, most recently by Ronald Reagan, that the United States and Iran actually were embroiled in something akin to war, and that those in the captured embassy could be better considered "prisioners of war" than hostages to militant captors. If so, what a strange kind of war, with journalists reporting daily both from the high command at home and from the enemy camp, using transmission facilities furnished and controlled by the other side.

And what of the content of the reports? It would be wrong to say that journalists did the bidding of the militants, except in rare cases. Even that small minority of reports planned by the captors to propagandize American backfired, stoking public anger in this country instead of sympathy for the Iranian cause.

The greater problem in the majority of both television and print reporting was lack of context. Lacking prior experience or knowledge of Iran, its access sharply limited or cut off, goaded by competion for the most obvious and dramatic stories, the press tended to focus tightly on the Americans and their immediate plight, without much emphasis on or explanation of the internal Iranian setting which brought about the event and made it so difficult to resolve.

With some notable exceptions, the press was trapped in the technology and deadline pressures of a story which took on a life of its own. For example, the hostages in the embassy were rarely seen, but the networks trained their cameras day after day on the shouting, fist-shaking mobs on the street just outside. A study by Associate Professor David L. Altheide of Arizona State University reported that the network evening news programs, in 10 sample periods over eight months, beamed Iranian crowds and demonstrations into American homes on 60 occasions, compared to only three interviews with unofficial, non-demonstrating Iranians who might have explained what the crowds were screaming about.

And what for the future? What does the "hostage crisis" and the reaction to it portend?

The greatest underlying question is how a democratic country with worldwide interests and responsibilities can cope with a world of trouble and turbulence in the 1980s. Will the leadership and people of the United States find a way to respond to outrageous actions without becoming, in the common phrase, hostage to events?

President Reagan's pledge of "swift and effective retribution" in case of threats to Americans abroad is clearly meant to provide deterrence against attach as well as reassurace to a deeply troubled people. Yet, given the profusion of incidents throughout the world, there seems little likelihood that Reagan's warning will turn back the tide of disorder.

There is little evidence that the Iranians who seized the embassy and its personnel, or other terrorists who have dramatized their causes with violent acts, acted on a calcuation of personal risk. In fact, the likelihood of direct engagement by the United States could spur some groups to greater risks for greater glory and more radical outcomes.

A prophetic report written for the Air Force in 1977 by Guy J. Pauker, a noted political scientist, projected "a period of increased social instability" in the 1980s, including the possiblity of a breakdown of international order he called "a world order crisis." Pauker foresaw difficult decisions for the United States. "In some instances, it may have to give priority to world order considerations, while in other situations it may have to defend narrowly defined national interests," he wrote.

"In deciding to use military force for the protection of limited national interest, a great power which is also a democracy has to be responsive to a wide range of considerations. Should the U.S. government be prepared to project its power into all parts of the world where Americans may wish to travel, trade, study or engage in any other normal and peaceful activity, in order to protect them? If not, where should one draw the line? Pauker asked.

A journalist who has observed government and public opinion during the Iranian drama emerges with few sure answers for future tests. But I have these suggestions:

First, the government should be prepared to meet the unexpected and intolerable with contingency plans for quick response, political as well as military, as troubles arise. The greatest impact as well as the greatest chance to affect the course of turbulent events is in the early hours of a crisis, when it is also most difficult to plan and see ahead.

Second, the press and the people, as well as those citizens who are also government officials, should keep their cool in the fact of provocation. This would provide the maximum flexibility for a national response which will be tailored to the reality rather than the emotional impact of the problem.

Third, everyone should become aware as soon as possible of the context and circumstances of a thunderbolt from abroad, without necessarily accepting the premises of those who have hurled it. Americans must understand as well as feel what is going on.

Finally, and perhaps most immediately important, the government, press and people of the United States have an urgent need to examine and reflect upon the events and impressions of the past 14 months. For all the courage of the hostages and the euphoria and unity of homecoming, this country cannot afford a repetition of what it has just been through. Yet, unless I miss my guess, many dangerous and dramatic trials, some within camera range, are ahead in the troubled decade of the 1980s.