When Giulio Andreotti, then Prime Minister, uttered the word 'Gladio' before Parliament in 1990, Italy discovered that it had been living with a secret of considerable importance for decades. Until then, 'Gladio' had been a name known only to a few insiders: it referred to a clandestine structure, created during the Cold War, which was supposed to spring into action in the event of a Soviet invasion.

To understand why it came about, we need to go back to the post-war period. Europe was divided into two blocs, and Italy, characterised by a strong communist presence and political fragility, was considered a weak link in the Western chain. In Washington and Brussels, there was fear that the Red Army could spread to the Mediterranean, or that the Italian Communist Party, at the time the strongest in Western Europe, could come to power. The idea was therefore to create secret resistance networks, ready to fight the communist forces. This was the context in which Gladio was born, formally under NATO control but managed in Italy by SIFAR (later SID and SISMI). Its members were civilians and military personnel trained at special bases, such as Capo Marrargiu in Sardinia, and received instruction in guerrilla warfare, sabotage and clandestine communications. Hidden in various locations around the country, secret depots of weapons, explosives and radio transmitters had been set up for use in the event that Italy fell under occupation.

For years, Gladio remained in the shadows. Then, in the 1970s and 1980s, growing political violence and terrorism gave rise to disturbing suspicions: some magistrates and journalists hypothesised that the organisation had played a role in the so-called 'strategy of tension', i.e. the use of fear and violence to influence democratic life. The name Gladio began to appear in investigations into the massacres, fuelling doubts and conflicting theories. When Andreotti officially admitted its existence in 1990, the news caused a sensation. It came as a shock to the public: for decades, alongside the official institutions, there had been a parallel network of armed, trained and secret men. Controversy immediately arose: was it really just a defensive structure, as its leaders claimed, or did it also play an internal role in Italian politics?

In any case, the word 'Gladio' continues to evoke the idea of an unsolved mystery. A reminder that the Cold War was not only fought on official fronts.