Challenged by terrorist tactics and guerrilla warfare in Iraq, the Pentagon recently held a screening of "The Battle of Algiers," the film that in the late 1960's was required viewing and something of a teaching tool for radicalized Americans and revolutionary wannabes opposing the Vietnam War.

Back in those days the young audiences that often sat through several showings of Gillo Pontecorvo's 1965 re-enactment of the urban struggle between French troops and Algerian nationalists, shared the director's sympathies for the guerrillas of the F.L.N., Algeria's National Liberation Front. Those viewers identified with and even cheered for Ali La Pointe, the streetwise operator who drew on his underworld connections to organize a network of terrorist cells and entrenched it within the Casbah, the city's old Muslim section. In the same way they would hiss Colonel Mathieu, the character based on Jacques Massu, the actual commander of the French forces.

The Pentagon's showing drew a more professionally detached audience of about 40 officers and civilian experts who were urged to consider and discuss the implicit issues at the core of the film - the problematic but alluring efficacy of brutal and repressive means in fighting clandestine terrorists in places like Algeria and Iraq. Or more specifically, the advantages and costs of resorting to torture and intimidation in seeking vital human intelligence about enemy plans.

As the flier inviting guests to the Pentagon screening declared: "How to win a battle against terrorism and lose the war of ideas. Children shoot soldiers at point-blank range. Women plant bombs in cafes. Soon the entire Arab population builds to a mad fervor. Sound familiar? The French have a plan. It succeeds tactically, but fails strategically. To understand why, come to a rare showing of this film."

The idea came from the Directorate for Special Operations and Low-Intensity Conflict, which a Defense Department official described as a civilian-led group with "responsibility for thinking aggressively and creatively" on issues of guerrilla war. The official said, "Showing the film offers historical insight into the conduct of French operations in Algeria, and was intended to prompt informative discussion of the challenges faced by the French." He added that the discussion was lively and that more showings would probably be held.

No details of the discussion were provided but if the talk was confined to the action of the film it would have focused only on the battle for the city, which ended in 1957 in apparent triumph for the French with the killing of La Pointe and the destruction of the network. But insurrection continued throughout Algeria, and though the French won the Battle of Algiers, they lost the war for Algeria, ultimately withdrawing from a newly independent country ruled by the F.L.N. in 1962.

During the last four decades the events re-enacted in the film and the wider war in Algeria have been cited as an effective use of the tactics of a "people's war," where fighters emerge from seemingly ordinary lives to mount attacks and then retreat to the cover of their everyday identities. The question of how conventional armies can contend with such tactics and subdue their enemies seems as pressing today in Iraq as it did in Algiers in 1957. In both instances the need for on-the-ground intelligence is required to learn of impending attacks. Even in a world of electronic devices, human infiltration and interrogations remain indispensable, but how far should modern states go in the pursuit of such information?

Mr. Pontecorvo, who was a member of the Italian Communist Party, obviously felt the French had gone much too far by adopting policies of torture, brutal intimidatio and outright killings. Though their use of force led to the triumph over La Pointe, it also provoked political scandals in France, discredited the French Army and traumatized French political life for decades, while inspiring support for the nationalists among Algerians and in much of the world. It was this tactical tradeoff that lies at the heart of the film and presumably makes it relevant for Pentagon study and discussion.

But this issue of how much force should be used by highly organized states as they confront the terror of less sophisticated enemies is far from simple. For example, what happens when a country with a long commitment to the Geneva Convention has allies who operate without such restriction.

Consider the ambivalent views over the years of General Massu, the principal model for the film's Colonel Mathieu.

In 1971, General Massu wrote a book challenging"The Battle of Algiers," and the film was banned in France for many years. In his book General Massu, who had been considered by soldiers the personification of military tradition, defended torture as "a cruel necessity." He wrote: "I am not afraid of the word torture, but I think in the majority of cases, the French military men obliged to use it to vanquish terrorism were, fortunately, choir boys compared to the use to which it was put by the rebels. The latter's extreme savagery led us to some ferocity, it is certain, but we remained within the law of eye for eye, tooth for tooth."

In 2000, his former second in command, Gen. Paul Aussaresses, acknowledged, showing neither doubts nor remorse, that thousands of Algerians "were made to disappear," that suicides were faked and that he had taken part himself in the execution of 25 men. General Aussaresses said "everybody" knew that such things had been authorized in Paris and he added that his only real regret was that some of those tortured died before they revealed anything useful.

As for General Massu, in 2001 he told interviewers from Le Monde, "Torture is not indispensable in time of war, we could have gotten along without it very well." Asked whether he thought France should officially admit its policies of torture in Algeria and condemn them, he replied: "I think that would be a good thing. Morally torture is something ugly."

At the moment it is hard to specify exactly how the Algerian experience and the burden of the film apply to the situation in Iraq, but as the flier for the Pentagon showing suggested, the conditions that the French faced in Algeria are similar to those the United States is finding in Iraq.

According to Thomas Powers, the author of "Intelligence Wars: American Secret History From Hitler to Al Qaeda": "What's called a low-intensity war in Iraq brings terrible frustrations and temptations - the frustrating difficulty of finding and fixing an enemy who could be anyone anywhere, and the temptation to resort to torture to extract the kind of detailed information from prisoners or suspects needed to strike effectively. How the United States is dealing with this temptation is one of the unknowns of the war. We are told that outright torture is forbidden, and we hope it is true. But as low-intensity wars drag on, soldiers tell themselves, `We're trying to save lives, no one will ever know, this guy can tell us where the bastards are.' "

If indeed the government is currently analyzing or even weighing the tactical choices reflected in "The Battle of Algiers," presumably that is being done at a higher level of secrecy than an open discussion following a screening of the Pontecorvo film. Still, by showing the movie within the Pentagon and by announcing that publicly, somebody seems to be raising issues that have remained obscure throughout the war against terror.