MANILA, March 4 — At the point of highest tension this past week, as troops and armored vehicles took positions at a military camp, a burly marine stepped forward and declared, "The only thing we want is a clean election."

It seemed a surprising thing to say at a moment when the country was poised for one more in a long string of coup attempts.

But in its coded meaning, it embodied the grievances, the idealism and the adventurism of a politicized military that has kept the Philippines on edge for the past 20 years.

That standoff last Sunday night ended peacefully, and any plans for a coup have been blunted for the moment. But experts on the military say that nothing has changed in the dynamics of plotting coups and that the pattern of destabilization is sure to continue.

Since the foiled coup that set the stage for the people-power uprising in 1986 and led to the ouster of Ferdinand E. Marcos from the presidency, these coups, coup attempts and unsettling coup rumors have been part of what might be called the Philippine version of democracy.

Each new generation of young officers seems to replicate the reformist passion and sense of mission — and sometimes the tactics — of those who went before.

Two of the past five presidents have been ousted by what amounted to civilian-backed military coups. Two others owe their presidencies to the same coups. The only one who entered and departed without military intervention was himself a general.

Along the way there have been innumerable feints and jabs by groups of junior officers whose youth and sense of mission sometimes made them vulnerable to manipulation by civilians with political agendas.

As a result, every Philippine president in effect serves at the pleasure of the military, and for every president, the care and feeding of senior officers is an important part of the job.

President Gloria Macapagal Arroyo has ostentatiously struggled to hold the loyalty of the generals, giving eight of them, one after the other, a chance to be chief of staff in the past five years.

This has been a crucial exercise for her because she was handed the presidency in 2001 when the military "withdrew its support" from her predecessor, Joseph Estrada, who had won office through the ballot box three years earlier.

"Withdrawal of support" has since become a code word for a coup, and a week ago she declared a state of emergency and began a series of arrests after factions of that same military in effect withdrew their support from her. She ended the state of emergency on Friday.

The spark for some of the troops this time, as the burly marine said Sunday night, was the question of "clean elections." The marines have been angry since 2004 when, according to many accounts, Mrs. Arroyo corrupted their ranks by enlisting their generals to manipulate her re-election.

That grievance is the latest sign of the corruption, patronage and abuse of power, in both the military and society at large, that has been at the root of much of the discontent in the armed forces.

Because of these abuses, the soldiers say, they are poorly armed, poorly trained, poorly paid, poorly fed and left to die on the country's battlefields while many generals in Manila grow rich at their expense.

"They feel the world is not fair," said Marites Danguilan Vitug, editor in chief of Newsbreak, a magazine that has examined the dynamics of the military. "They pledge that they'll repair the military if they get in command."

The adventurism arises from a special sense of mission that found heroic expression in 1986 and has animated the military ever since, said Senator Rodolfo Biazon, a former marine who now runs the Senate Committee on National Defense.

The Philippine Constitution itself is part of the problem, he said.

"There is a provision that has always been invoked in these coups, that a soldier is the protector of the people and the state," he said. "So the impression is that they have the right to judge the government, and if the national leader fails to measure up to what they expect, it is their duty to replace that leader."

As a result, along with training and fighting, the ranks of the military are constantly alive with political discussions and often with plots and plans.

"This is at the bottom of things," Senator Biazon said, "and I do not know how to provide a solution."

The high standards taught at the Philippine Military Academy, or P.M.A., may, perversely, play into this problem. They are so at odds with the day-to-day culture of the Philippines that a clash seems almost inevitable.

A presidential commission investigating a failed coup attempt in 2003 put it this way: "There is the idealism taught at the P.M.A. which is later challenged by the realities of combat duty and life in the real world.

"This creates a powerful emotive force that when combined with the issue of graft and corruption and the poor conditions in the field, could make soldiers vulnerable to recruitment by both military and civilian coup plotters."

A culture of leniency — in which some coup participants have been punished only with a set of push-ups — also helps to ensure that the ranks of the military are permeated with politicized officers.

"There's no punishment that would be a deterrence to coups," said L. Scott Harrison, an expert on the military who is managing director of a consulting group, Pacific Strategies and Assessments.

"Maybe house arrest or detention in a military facility, and then after a while amnesty, and you have your 15 seconds of fame to boot," said Mr. Harrison, who is based in the Philippines.

The most famous soldier in the Philippines — and to some junior officers the most admired — is former Col. Gregorio Honasan, who led the coup attempt in 1986, became a senator and is now in hiding, accused by the government of involvement in the latest disorders.

Veterans of other coup attempts have continued to rise through the ranks into ever more senior positions, and some of their names have also been linked with these events.

When a formal investigation into corruption in the 2004 election went nowhere, said Glenda Gloria, an expert on the military, the pressure built again within the armed forces.

"An outburst was inevitable," she said. "It had to happen."

All the while, Philippine soldiers, underfinanced, poorly trained and indifferently commanded, are in the field fighting three wars — against a Communist revolution, a Muslim insurgency and a vicious band of fighters called Abu Sayyaf.

As if that were not enough, Ms. Gloria said, the military is preoccupied with a fourth war that seems just as intractable, within its own ranks.

Carlos H. Conde contributed reporting for this article.

Copyright 2006The New York Times Company