The increasingly violent struggle between die-hard rightists and radical leftists is making anarchy a way of life in El Salvador.

As this Central American country's political, social and economic life continues to disintegrate, there are mounting fears that this anarchy may be only a foretaste of a full-scale civil war to come.

Daily, one encounters implausible characters and improbably horrible events that go virtually unremarked here and are merely part of the surreal spectacle of day-to-day existence on the brink of disaster.

El Salvador has become a country where radical leftist groups stage protests that look like homecoming parades in the American Midwest, replete with brightly colored pompoms, buglers and drummers -- except that the teen-agers directing the crown have guns in their book bags and the banners that lead the march call for "prolonged popular war or nothing."

Amid the festivity everyone knows that if the police or Army appear there will be a bloodbath. It has happened so many times before. The marchers are frightened. The police and soldiers are frightened. Somebody is bound to start shooting -- and the soldiers have better guns, at least for the moment.

The marchers go on, just the same, sometimes drawing thousands of people.

A middle-aged man walkes into a hotel lounge and puts his wrist bag on the bar with a heavy thud, the butt of a .38 caliber revolver protruding from it. No one pays much attention. Guns have become so commonplace in El Salvador that a sign at the airport advises departing passengers that they are beieng screened lest they "accidentally" carry their firearms on board the plane.

This particular man at the bar said he needed the pistol at his wrist, and the Israeli submachine gun he carried in his car, because he had made a lot of money in El Salvador and his views made him a target of the left.

Where does this man stand in the country's fractionalized ideological spectrum?

"I'm not a capitalist and I'm not a communist," he said. "I'm a national socialist. You know, a Nazi."

He and others like him feel, he said, that the United States is making a tremendous mistake by backing the ineffectual civilian-miltary coalition government that has been promising reforms and peace without achieving either.

"We must kill all the snakes," he said. Joining with like-minded forces in Guatemala, who understood the real threat posed by communists, he and his friends would put an end to communism in Central America and save the United States from itself -- "If the U.S. will stay out of our way."

From the far right to the far left, Salvadorans tend to be tremendously proud and fiercely nationalistic.

They live in a physically beautiful country of high volcanic mountains, dazzling blue lakes and broad black beaches looking out on the Pacific. They are known as a determined and hard-working people.

Everyone assumes that if there is civil war, it will be terribly bloody. Forty-eight years ago, when the population was only a quarter of today's, 30,000 people died in the suppression of the hemisphere's first communist revolution.

The country is small and crowded: 267 miles long and 112 miles wide, with 5 million people now crammed inside its borders. There would be no place to hide.

Demographies, moreover, are at the root of many of El Salvador's problems.

Half the people are under 17, and young people see very little future for themselves if the country's economic and political structures, where both power and wealth are in the hands of a miniscule minority, continue as they have for as long as their parents can remember. According to local officials, for instance, 70 percent of the best land in the country is owned by 300 families.

It is not surprising that the national university is the headquarters for most of the country's radical leftist groups.

Those who try to take a middle road between the extremists become the objects of attack from both sides. Even acts of charity are condemned.

A priest who found several bloated bodies of torture victims washed up on the beach near his church was warned by local authorities to ignore them. When finally, after several days, he went ahead and burned the mutilated corpses, he was denounced by the left for failing to fingerprint them so that they might be identified as persons abducted and killed by the armed forces.

El Salvador's newspapers and airwaves are filled with the conflicting voices of revolution and reaction as leftist and rightist groups buy advertisemenets to make their views known. One of the strongest voices for moderation has been Catholic Archbishop Oscar Arnulfo Romero, whose sermons are broadcast by a church-owned radio station.

The building housing the station was blown to bits by right-wing terrorists earlier this month.

The young military officers who last October ousted the generals who had ruled the country for decades professed their intentions of both leading the country out of its morass of fear and preserving the integrity of the Army.

The young officers said they wanted to fight communism by implementing basic reforms, alleviating the legitimate grievances of the people while mounting a serious counterinsurgency campaign against Marxist guerrillas.

The United States, fearing El Salvador was headed toward a Nicaragua-style revolution and leftist takeover, immediately jumped to support the new government, promising nearly $50 million in aid to support the reforms and another $5 million to $10 million to help fight the guerrillas.

But even talk of the as yet unimplemented reforms has infuriated the right, and the counterinsurgency efforts have tended to look like brutal, often indiscriminate oppression of the left.

In the current atmosphere of chaos, many people are simply giving up on El Salvador. Some of those may be the people most needed by the country.

A young surgeon from San Salvador's largest hospital recently sat and talked about his job after putting in a 36-hour shift.

Mostly he deals with bullet wounds, the doctor said. Each day he finds himself trying to repair the damage wrought by extremists of the left and right.

Once, he said, he saved a patient only to have him abducted from the hospital and never seen again.

He looked around. He didn't want to talk about it anymore.

The young doctor's mother and sister have already gone to Miami to escape the country's troubles. He hopes to leave soon as well. Other surgeons, he said, will have to be found to take care of the wounded and the dying.