Few crimes of this era have carried such unwanted but powerful symbolism as the attempted assassination of Pope John Paul II by a fugitive murderer whose natie land, caught between East and West, has searched painfully through all its years for a lasting identity.

To consider Mehmet Ali Agca, accused of shooting the spiritual leader of the largest Christian flock in the West, is also to consider Turkey, a nation founded just 58 years ago by Mustafa Kemal Ataturk on the conviction that to survive, his people could only adapt their ancient Islamic ways to European civilization "with both its roses and its thorns."

The hijacking today of a Turkish airliner, by what the government said were ultraleft terrorists, put this country's political violence in the world spotlight again, just 11 days after the attempt to kill the pontiff.

To fulfill Ataturk's vision and forge this nation into a modern secular state, a succession of rulers have had to deal with potent conflicting forces of Western modernism and traditional Eastern ways that buffeted Agca during his impoverished upbringing in the provincial city of Malatya, 500 miles southeast of here, and that shape the lives of 45 million Turks.

The task is immense, ranging far beyond the question that has preoccupied the West since World War II, that of Turkey's position as a stanuch NATO ally, strategically positioned between Europe and Asia.

The United States and some of its West European allies are moving to strengthen Turkish fighting forces in the context of the Soviet invasion of Afghanistan, the Iranian revolution, and the Iranian-Iraqi war. This does little to diminish the social, cultural, political and economic problems facing Turkey's military government, which took power last September after political terrorism by young men like Agca had brought the country to the brink of civil war.

When the generals led by Chief of Staff Kenan Evren seized power, more than 2,000 Turks a year were dying under the guns and bombs of factional strife. But martial law was extended from 20 to 67 provinces, mass arrests began and strikes were banned. Today, with about 26,000 jailed, most of them left-wingers, and mass military trials under way in several cities, Turkey is calmer than at any time since the mid-1960s, according to journalists here.

Thirteen persons died in political violence in one recent week, it was reported, a two-year low. The authorities say they have collected more than 300,000 arms, most voluntarily turned in by people relieved to be rid of them. A curfew from 1 a.m. to 5 a.m. stops all but interprovince traffic.

Turks at every level of society talking with a traveler here in the past week expressed relief at this state of affairs. Even Agca's 50-year-old mother, Muzeyyen, in an interview in Malatya last week, tearfully said, "If Evren had become our leader three years ago, what has happened to me would not have happened. Many mothers would not have lost their lambs. Let him always be our leader. Where have you been, Kenan Evren?"

But it is an uneasy peace, enforced by the military from above, which may not reflect the truer nature of Turkish society today. Government officials and other seasoned Turkish and foreign observers seem sure that despite the arrests, the capacity for terrorism has only been driven underground, or abroad.

More than 25,000 Turks have left since the coup, and hundreds of them are thought to be terrorists, who, like Agca, will submerge in the huge expatriate Turkish population in Western Europe and lie dormant, perhaps for years to come. At home, the Turkish press still reports new acts of violence, the discovery of new cells of left or right, new caches of arms.

Terrorism, part of the past with which Ataturk sought to break, began here in tribal vendettas, religious strife between Sunni and Shite Moslem sects, and clashes of the dominant Turks with the estimated 7 million Kurds. The Kurds are concentrated in the southeast, where feudalism continues, and local agas sometimes own dozens of villages outright.

Turkey's social and economic woes of the last five years fired this violence with destructive heat: unemployment of up to 20 percent, inflation that has exceeded 100 percent in some years, rural migration to the cities, now ringed by peasant-built ghettos whose lights at night "resemble the fires of an invading army," as one man put it.

In such conditions, neofascist organizations such as the National Action Party and fundamentalist Islamic groups such as the National Salvation Party, whose leaders are now in jail, found fertile ground.

The National Action Party claimed to represent Turkish nationalism, and it is said that its youthful followers, who call themselves "Gray Wolves" and who have perpetrated much of the right's violence against the left, used to gather clandestinely to howl like wolves when leader Alparslan Turkes appeared.

The National Salvation Party gathered strength among tradionalist groups. Last August, just before the coup, it staged a rally of about 80,000 followers in Konya, Turkey's religious capital. They carried banners in outlawed Arabic script demanding an end to Ataturk's secularism, and wore banned turbans. Smoldering resentments like these cannot be extinguished by force from above, and the generals know it.

So new efforts at land reform are about to be launched in the southeast, the currency has been devalued, virtually eliminating a once-thriving black market, and prices of such staples as cigarettes, gasoline and other items are being rasied to bring the economy more into line with the harsh reality of a country that must import most of its petroleum.

Much progress has been made from the dark days of the winter of 1979-80 when, saddled with ballooning foreign debt, Turkey ran short of heating fuel. Thousands suffered long weeks without heat, and senior government officials worked in their overcoats.

Inflation has been cut to about 40 percent this year. Employment is up. But it has taken a suspension of democracy to achieve, and it is here that Turkey feels again its estrangement from the West it seeks to emulate.

Some European law makers have condemned the suspension of the legislature here as well as the covert, but real pressure against the press, and the awaited naming of a new constituent assembly by the military government to draw up a new constitution.

The Evren-run National Security Council refuses to set a date for resumption of political activity. Evren has not ruled out political aspirations of his own, leading to suspicions that a strong, perhaps military-style regime, is in the cards. There is evidence he would win hands down at the polls.

Officials attempt to combat suspicions that the generals strengthened their hands by waiting to intervene until the crisis had peaked. These officials point out that the military warned the politicians months before to cooperate to end the terrorism, adding that the suspended Assembly's records showed more than 1,200 bills stalled in committee.

It is clear the controversy over civil liberties cuts deepest in the Turkish psyche over allegations in the West that the military condones torture in its prisons. This contention is supported by accounts of atrocities.

"You call us barbarians," said one pro-Western provincial official recently, "but I have made a study of torture in history and all the Western countries tortured people in their early days. They have forgotten this."

Foreign Minister Iltar Turkmen, a soft-spoken career diplomat, asserted that "we are trying to take a relaxed view, welcoming all" legislators interested in seeing the situation firsthand.

Three factors affect the timetable for the return of democracy, Turkmen said: the period needed to draft a new constitution, the issue of how to "reactivate political life," and the fight against terrorism.

Jet-age travel, the easy access to guns, shadowy connections among terrorist groups in similar remote places of the world, can make the social unrest in a country like Turkey a lethal reality far from its borders, as the Agca case and today's hijacking show.