Recently, after a number of letters addressed from here to the Vatican denounced him as corrupt, a terrorist, an agent of the devil and a Marxist, El Salvador Archbishop Oscar Romero decided to pay a visit to the pope.

"I wanted to clarify some of the things they have been saying," Romero, 60, said in a recent interview.

The pope, he said, "knows that people are trying to reclaim their rights" in El Salvador, and that the local Catholic church has been among their firmest supporters.

"He understands, he approves," Romero said. "He told me to keep trying to avoid violence."

Despite Romero's efforts and the will of Rome, however, violence between El Salvador's military government and a wide spectrum of opposition forces is on the upswing and both sides expect it to get worse.

When local politicians and U.S. diplomats talk about El Salvador, the word they most commonly use is "polarized." Having lived under military rule for 46 years, and having had one of the Third World's most feudal economics for much longer, Central America's smallest, most crowded country is on the verge of explosion.

The polarization is of the traditional type, pitting rich against poor, right against left and military against civilian in a series of bloody battles that since early last year have resulted in the death or disappearance of hundreds of peasants, a number of wealthy businessmen, a government minister and at least two priests.

On one side of the battle is the military, led by President Humberto Romero (no relation to the archbishop), an army general whose election in February of last year was widely considered to be the most flagrantly fraudulent in a long history of rigged contests.

The military maintains control in conjunction with a number of paramilitary rightist propaganda and vigilante groups. Among them is ORDEN whose acronym spells the Spanish word for "order", a 65,000-strong civilian security force dedicated to the "preservation of democracy" and headed by an active-duty army officer.

The military traditionally has been kept in power by the country's economic elite, a group of 20 or 30 families who own approximately 60 percent of El Salvador's land and industry. A knowledgeable State Department official recently described it as "the most reactionary private sector of any country in the world."

On the other side are a number of organizations of varying degrees of militancy ranging from unions and government-emasculated parties pressing for reforms to peasant groups and terrorists who advocate immedate government overthrow.

In an abrupt rejection of its centuries old alliance with the oligarchy, most of El Salvador's Catholic bierarthy, including Archbishop Romero, has thrown its power behind the call for nonviolent reforms, including a total redistribution of the country's land.

Both sides agree that it was largely the impetus provided by the church that brought the long-festering polarization into the open by legitimizing claims for reform in the eyes of the peasants.

Several peasant groups, which are prohibited by law, including the Catholic-backed Christian Federation of Salvadorean Peasants have joined student groups to form the People's Revolutionary Bloc, a militant front that increasingly advocates violent change.

A clash in March between Revolutionary Bloc and ORDEN at the village of San Pedro Perulapan left 20 peasants dead, by government count. Following government publication of an account that blamed the peasants for provoking the incident, Archbishop Romero, in an unprecedented act, published his own version of the incident charging ORDEN with provocation, torture and murder.

Ostensibly neutral in the ongoing warfare is the United States, which each side blames for supporting the other.

"The opposition is sustained by Carter's human rights policy," said a wealthy business leader. "The extreme left, the church, the terrorists have taken liberties they wouldn't have taken before. They feel that they have the backing of the U.S. States Department to commit acts that go unpunished."

But an opposition political leader says: "The United States says it opposes human rights violations here, yet it still doesn't have a clear view of the mechanisms that can be used to combat them. They used a million covert and overt ways to fight communism here. Why can't they fight with us now?"

What the United States has been doing in El Salvador has been questioned in both countries.

Following numerous reports of rights abuses by the Salvadorean government, the State Department decided in May of last year to oppose a $90.4 million Inter-American Development Bank loan to build a large dam here. Rather than be turned down, El Salvador withdrew the loan application.

In October, the State Department approved a new application for the loan on ground that the situation here had improved. Cited as improvements were the new Romero government, inaugurated in July of last year, and its lifting of a state of siege and a ban against an opposition newspaper.

The approval was given despite the strong objections of State Department Human Rights Coordinator Patricia Derian's staff, which said the changes were merely cosmetic.

Less than a month later, in November, Romero reimposed a virtual state of seige with a law for the "Defense and Guarantee of Public Order," a draconiam document that prohibits virtually all meetings, organizations or publication of anything the government finds unpleasant. The law also prohibits Salvadoreans from providing "any type of resources to foreigners or foreign organizations" - including journalists, embassies or congressmen - that would offend the government.

Continuing its up and down response to the human rights problem in El Salvador, the State Department in January organized a trade conference in New Orleans, designed to promote business between U.S. and Central American companies. President Romero was invited as one of two keynote speakers. The other speaker was the chairman of the U.S. government-run Export-Import Bank, who told El Salvador and other Central American governments that the bank was eager to lend them money.

Following the Perulapan incident in March, however, the State Department sent a member of Derian's staff, along with Deputy Assistant Secretary Sally Shelton here for an investigation. They found that the human rights situation had deteriorated, and that whole villages were terrorized by ORDEN spies and the army, who treated any calls for reform as communist-inspired subversion and indulged in widespread torture and illegal imprisonment.

In a recent interview, Lt. Col. Rafael Flores Lima, President Romero's press spokesman, said that while the government recognized land distribution problems as most pressing, it had no plans to recognize the peasant organizations.

Instead, he said, the government planned a new fund to distribute low-term loans to peasants wanting to rent land.

Since there is little land available to rent, Flores Lima admitted there could be some problems with the rich oligarchs.

"They would like the government to behead anyone who has an idea different from theirs," he said.