Pride Pushed Peru, Ecuador Into Their Lethal Border Clash : Latin America: Minor incidents were an annual tradition. But both nations have now crossed the line. Analysts fear escalation into a broader war.

The scene of the border conflict between Ecuador and Peru could be a picturesque park of rugged mountains, dense rain forest and winding rivers. Troops from both sides, in scattered military posts, have turned the remote wilderness into a turbulent combat zone.

They have clashed before, but not with such deadly force since the two countries fought a territorial war in 1941. Peru won then, and Ecuador still aches from the loss of its claim to a huge hunk of land in the Amazon Basin.

About 50 miles of postwar border has remained unmarked because of disagreement over where the line should be. And that line is what the recent fighting has been about.

Diplomats from the United States and three South American countries have mediated marathon peace negotiations in Rio de Janeiro since Tuesday.

But a cease-fire has remained elusive as both sides have proffered conflicting conditions for an end to hostilities.

It seems to be a classic case of two proud opponents who stubbornly refuse to compromise for fear of losing face.

But if the conflict is not settled soon by negotiation, some analysts fear that it could escalate into a broader war with enormous losses. It has already cost at least 20 lives and hundreds of millions of dollars.

Almost every year, Ecuador revives the territorial dispute, often with minor incidents involving troops from both sides of the disputed border area. The incidents traditionally occur in January, the anniversary month of a 1942 pact that confirmed Ecuador’s bitter loss in the war.

“What happens in January is a ritual, a ritual for two--it’s a dance,” said Jorge Richarte, a Peruvian social scientist in Quito with a Latin American research institute.

How incidents this year escalated into more than a week of armed conflict may never be known. Each side insists that the other invaded its territory. Richarte and other analysts offer several possible scenarios:

* Ecuadorean forces, perhaps intending to trigger a minor incident as a reminder of their territorial claim, may have been surprised by a major Peruvian reaction aimed at ending the annual ritual once and for all.

* Peru, which has long demanded the final demarcation of the disputed border, may have ordered its troops into Ecuadorean-occupied land to force the issue. If that happened, the Peruvians were probably surprised by Ecuador’s readiness and strong resistance.

* An unplanned confrontation between nervous troops may have triggered shooting on one side, provoking anger on the other and more shooting that went out of control.

Ecuador claims that since Jan. 27, Peru has repeatedly assaulted jungle posts that Ecuadorean troops have occupied for years, while Ecuador’s troops have not attacked any Peruvian position.

Peru says its forces are trying to dislodge Ecuadorean troops from recently occupied positions in Peruvian territory.

Both sides have rushed reinforcements into the area. Either before or during the conflict, Ecuador seeded the jungle terrain around its positions with land mines. Peru sent helicopter gunships and jet fighters to support its ground troops.

By Saturday, each side had officially acknowledged the loss of nearly a dozen men in the fighting. Officers on each side claimed that scores of the other side’s soldiers had been killed.

News media in Ecuador have fueled a fiery explosion of nationalist fervor. Even President Sixto Duran Ballen’s political opponents have joined him in vowing that “not one centimeter” of territory will be ceded to the “invaders.”

“There is a whole cult of nationalism here that now has reached the point of xenophobia,” said Eduardo Bedoya, a Bolivian anthropologist who lives in Ecuador.

Peruvian President Alberto Fujimori also has overwhelming support at home for his drive to turn Ecuadorean forces out of land claimed by Peru.

It seems to strike hardly anyone as irrational to be spilling blood over the precise location of a borderline through 50 miles of undeveloped wilderness on the two countries’ 1,000-mile border. That the area contains gold and possibly oil is not the point. It is more a matter of national honor and dignity.

Ecuador has adamantly refused to budge from army posts in the valley of the Cenepa River, a tributary of the Upper Amazon. Access to the mighty Amazon is as sacred to this country as Manifest Destiny was to the United States in the 19th Century.

Peru insists that the 1942 Protocol of Rio de Janeiro, signed by both countries after the 1941 war, makes the Cenepa watershed Peruvian territory.

Lima ignores Quito’s arguments that Ecuador signed the protocol under duress and that the document is “unenforceable” because maps of the area were grossly inaccurate at the time.

In the current Rio negotiations, Peru has demanded the creation of a demilitarized zone as a condition for a cease-fire. Ecuador has called for an “unconditional cease-fire,” arguing that it cannot be required to vacate military positions it has held for years.

During the diplomatic standoff, both countries have suffered economic losses from the fighting. Analysts estimate that each government has spent hundreds of millions of dollars for military mobilization.

If the conflict frightens off investors and tourists, the long-term losses could be staggering for two countries that are struggling for economic development against handicaps of historic poverty and scarcity of capital.

If the conflict were to escalate into a wider war, Ecuador is likely to be hurt more. Its population and economy are about one-third of Peru’s, and its military power is far inferior. Peru’s army has years of combat experience from fighting the once-powerful Shining Path guerrilla movement.

The smartest thing for both countries, a European ambassador in Quito said, would be to declare a cease-fire, then take their time haggling over territory.

In Rio on Saturday, the talks appeared to be moving in that direction. “We have no idea of when we could reach an accord, but both countries have reaffirmed their desire for a peaceful solution,” a Brazilian spokesman said.