The Independent has unearthed a remarkable find in the National Archives:
A secret Foreign Office memo dated 6 May 1976, entitled Italy And The Communists: Options For The West, floated one possible course of action as "action in support of a coup d'etat or other subversive action". The authors admitted: "By its nature, a coup d'etat could lead to unpredictable developments." But they added that, in theory at least, "it could be promoted. In one way or another, the force of the right could be counted on, with the support of the police and the army". The idea of a coup to remove the PCI or stop it coming to power "could be considered attractive" – but the idea was rejected as "unrealistic". (Independent)
A coup might have been discounted, but the mechanism to promote one did exist, in the form of the NATO stay-behind network Gladio, revealed by Giulio Andreotti in 1990.