Cold War Secret: Allies’ Last Defense Line : West Europe: Several thousand anti-Communist spies and saboteurs were set for invading hordes.

Spy buffs and thriller writers discouraged by the vanished Berlin Wall and dying ideologies, take heart: There’s life in the old Cold War yet.

The East German Stasi is gone, the Soviet KGB is reduced to running beauty contests and Bulgarian umbrellas with poisoned tips are out of stock. But just when the plotting gets really rough, to the rescue ride NATO and the CIA.

Thanks to them, it seems that a secret army of several thousand trained anti-Communist spies and saboteurs have slumbered in the netherworld of Western European democracies for three decades as a last line of defense in a war that never came.

They were “stay-behind” operatives, trained for the unthinkable: a Communist invasion. Their mission was to rise up after occupation in the great tradition of the partigiani and the Maquis and to nip at the heel of the invading Soviet jackboot.

They were mostly civilians, and they were white hats, patient and patriotic good guys. Or were they?

They never fired a shot in anger. Or did they?

All over Western Europe, newspapers and opposition political parties are demanding to know more about the bizarre Cold War operation known in Italy as Operation Gladio.

In the absence of an invasion, was the secret force exploited in some countries as an arm of right-wing terrorism? Italy, particularly, wants to know, but so do other NATO countries.

In Belgium, where the current prime minister and defense minister disclaim any knowledge of a resistance network, a former defense minister said this week that he was aware of the existence of an underground group in his country. And in France, the current defense minister confirmed that an underground resistance network had existed there for many years.

Francois-Xavier De Donnea, Belgium’s defense minister from 1985 to 1988, said he was told “spontaneously” about the underground network when he took office. He doubted that there could have been links between the Belgian force and still-unsolved supermarket bombings attributed to right-wing terrorists in the early 1980s that claimed 28 lives.

The Belgian resistance group is moribund, De Donnea, said: “In the past few months it was reduced purely to maintaining communication systems. Exercises were scrapped, perhaps as long as one or two years ago.”

In Paris, the newspaper Liberation reported that the French network was formally dissolved only after recent disclosure of Operation Gladio in Italy. Defense Minister Jean-Pierre Chevenement said that the French network, conceived in the early 1950s to function as contingency liaison between an occupied country and a French government in exile, had been “dormant” for most of its existence.

Greece, Holland, Austria and Portugal also had stay-behind forces created at the height of the Cold War. So did Scandinavian countries, including neutral Sweden, according to news reports in Stockholm on Wednesday. Switzerland may also have had a group, and Turkey as well, according to other press reports Wednesday.

Retired Greek Gen. Nikos Kouris told the Italian newspaper Corriere della Serra that a Greek force was formed with CIA help in 1955 to intervene in case of Communist threat, whether external or internal. “There were ex-military men, specially trained soldiers and also civilians,” Kouris was quoted as saying. “What held them together was one ideological common denominator: extreme rightism.”

The German newspaper Die Welt reported Wednesday that U.S. intelligence agents helped organize the network, recruiting hundreds of guerrillas and planting weapons caches across Western Europe in the early days of the Cold War.

The Social Democrats, Germany’s main opposition party, call the super-secret project “the biggest scandal” in the history of the North Atlantic Treaty Organization. They demand to know if a German branch of the secret underground existed and whether it had links with right-wing extremists.

A German government spokesman, Hans Klein, confirmed Wednesday that plans existed for covert anti-Communist actions in case of war but said they had no direct connection to the West German armed forces.

“Reports that link the precautions mentioned with expressions like commando group or guerrilla army are false,” Klein said without elaboration.

The German Defense Ministry, like NATO itself, is so far close-mouthed about the behind-the-lines force, but in Italy, its existence has already provoked a major political crisis, triggering demands from the opposition Communist Party for the resignation of Prime Minister Giulio Andreotti.

It was Andreotti who indirectly disclosed the existence of Operation Gladio--the word is Italian for a double-edged Roman sword--late last month in a report submitted to Parliament in response to a judicial inquiry into a terrorist murder in Venice.

Subsequently, Andreotti told the Senate that 622 Italians had been members of the stay-behind force and trained by the Italian secret services. Weapons were hidden in 139 caches around the country. The Gladio forces were a resistance network made up mostly of right-thinking former military personnel, with women first admitted in 1978.

President Francisco Cossiga, for his part, said that, as a junior defense minister in the 1960s, he had helped develop an Italian force that Andreotti says was first formed in the 1950s.

Venice Magistrate Felice Casson, who wants to know if Gladio weapons were used in the 1973 murder of three policemen, has asked if Cossiga would testify about the force. No Italian president has been summoned to a judicial inquiry, but Cossiga, who says he was “honored” to help create it, says he has no objection.

In a nation where politics-by-conspiracy is the norm, the left speculates that members of Operation Gladio may have participated in several right-wing terrorist attacks that killed about 140 people between 1969 and 1980. Italian intelligence agencies, which controlled the Gladio network, have been accused of aiding right-wing terrorists in the 1970s.

“We ask that all this be fully investigated so that there are no dark corners, ambiguities, uncertainties or unresolved mysteries,” said Fabio Fabbri, Senate leader of Italian Socialists.