Public opinion polls and increasingly severe security measures suggest that a growing number of Italians are becoming more disenchanted with the way the country is run and more fearful about its future.

Despite years of talk of political and economic crisis, there is a general perception here and abroad that in recent months the overall Italian political situation has worsened sharply.

Recently, one nationally known observer, Antonio Gambino, raised the question in a column in the left-of-center independent Rome daily La Repubblica of whether Italy was likely to survive until 1982 with its political institutions intact.

Summing up the events of recent months -- a tax-fraud scandal involving the highly respected financial police, the Guardia di Finanza, a botched rescue and relief effort following the massive earthquake in the south, government indecision in dealing with Italian terrorists and a severe economic turnaround from 1978-1979 -- a high-ranking Western diplomat said: "People are running scared over Italy's future in a way they haven't done for quite some time."

The diplomat was referring to fears that current chaos will lead to early elections and a renewed show of strength by the powerful Communists, who, although they still constitute Italy's second-largest party, have suffered losses in two recent elections.

There is also evidence of a continued erosion in Italy's already stunted sense of national community. Italians traditionally produce a much heavier voter turnout than their American counterparts, and many here were shocked when last June's nationwide regional elections showed that 7.4 million Italians -- almost 17 percent of eligible voters -- either failed to vote or cast a blank ballot.

Although economists believe many Italians may indulge in illegal capital export or gold purchases, current economic statistics give no indication of a general loss of confidence in their country by Italians.

It appears, however, that attitudes toward the country's political system are becoming increasingly negative. Much of this come to the surface in ordinary conversation. A recent poll for Panorama magazine by the Demoskopea public opinion institute shows that 87.5 percent of those polled say they have little or no confidence in the country's political parties.

Compared with a sounding done in December 1979, the poll also indicated a 29 percent jump in the number of people who said they would cast blank ballots if elections were held at that time.

The poll also showed that Italy's two major parties, the ruling Christian Democrats and the Communists, had dropped in popularity since December 1979 and that only one politician, former premier Giulio Andreotti, inspired the confidence of more than 30 percent of those questionedd: 31.6 percent of those polled expressed confidence in the well-known Christian Democrat.

In addition, there is evidence that years of terrorist violence are finally leaving their mark on this basically unregimented society. For the first time in recent months, many large companies, newspapers and government agencies have set up security measures previously unknown here.

Many political parties, the headquarters of the Italian state radio and TV network, and the Italian national press agency now have set up video cameras at doorways and installed special police alarm buttons. The Interior Ministry recently allocated several hundred thousand dollars to buy about 50 new bulletproof cars, private sales of which have also soared among Italians worried about kidnaping or political violence.

The visibility of machine-gun-toting policemen wearing heavy bulletproof vests also is increasing. And tension among the country's security forces has caused incidents that further distress Italians already worried about the dangers of rising crime. Earlier this month plainclothes police on the lookout for terrorists in a Rome residential area shot and killed a 28-year-old woman riding in a car that ignored an order to stop.

The issues of public morality and earthquake relief have combined to produce a highly negative impression in many foreign capitals that contrasts sharply with the respect won in the first half of 1980 by then-premier Francesco Cossiga.

His successor, Arnaldo Forlani, is primarily a veteran of internal Christian Democratic politics.

"Forlani had a run of bad luck following his appointment as premier last September, but in general he seems less willing to make unpopular decisions," one Western diplomat said.

But the major impact of recent events has naturally been at home. "We may soon all be behind bars," said a 26-year-old communist writer who fears that chaos will lead to an authoritarian takeover.

Although in recent weeks the Communist Party appears to have finally closed the book on the so-called historic compromise -- its decade-old unsuccessful plan to reach power together with the Christian Democrats -- there still exists no practical alternative to 35 years of uninterrupted Christian Democratic rule.

The key swing party, the Socialist Party, is for the moment committed to an alliance with the governing party even if the Socialists' frequently renegade policies are a major cause of the government's growing instability.

Although Italy was until recently caught up in the most dramatic episode of terrorist violence -- the kidnaping of Judge Giovanni d'Urso -- since the kidnap-murder of former premier Aldo Moro in the spring of 1978, continued terrorism is only one aspect of the current malaise.

Italian democracy, after all, has managed to withstand years of politically motivated bloodshed without resorting to undue repression. What has been more troubling has been the indecisiveness of the government response. In part because of the Socialists' leaning toward a "soft line" opposed by the other coalition members, the four weeks of D'Urso's captivity were characterized by disturbing policy shifts.

The resurgence of left-wing terrorist last November -- after several months of a falsely encouraging hiatus, there have been four murders and the D'Urso abduction -- took place against an already worrisome backdrop.

First, the tax-fraud scandal came to involve disclosures linking a Christian Democratic Cabinet minister, who eventually resigned, to a controversial, muckraking journalist whose killing in February 1979 is still unsolved.

Already involved in a bitter debate on what Italians are now calling "the moral question," the Christian Democrats were further shaken when in December French police tracked down and arrested a much-wanted terrorist suspect whose father is one of the party's leading figures.

What cast the most discredit on the entire government, primarily on the Christian Democrats, was the inadequacy of the earthquake rescue and relief effort.

The earthquake not only disclosed the negligence and inefficiency of a political system designed more to perpetuate party power than to win popular consent through effective government; it also revealed the extent of Italians' distrust in the overwhelming majority of their leaders.

In the days following the quake, thousands of southern Italian emigrants poured back into the country convinced that, without them, their relatives would receive no real assistance.

Even more telling, all through Italy's north, people anxious to help made a point of turning to nongovernmental agencies because they believe that, as one Roman put it, "all politicians are thieves."

To an extent, then, the earthquake revealed both the suspected fragility of the current Italian system and the feelings of Italians toward those who govern them.

Francesco Alberoni, an Italian sociologist who writes frequently for the Milan daily Corriere della Sera, even went so far as to suggest, cynically, that given the absence of a functioning electoral system in which voters choose between alternating parties or coalitions of parties, an occasional earthquake is necessary here to point up the unhappy state of both government and society.