After having arrested the November 16, the enemy offensive in Cortellazzo, thus preventing the Germans and the Austrians from arriving in Venice and winning the European war on the wave of Caporetto, the Italian Navy returned to the offensive, continuing the own traditional strategy with more, this time, the precise intention to underline in everyone's eyes the will of the nation.
Already on November 18 a destroyer squadron, composed of Boldness, Abba, Ardente e animoso beats, early in the morning, the Austrian trenches at Revedoli with 600 cannon shots from 102 mm. The action, which raises the enthusiasm of the Italian troops and the ire of the Habsburg generals, is renewed the day after by the fighters Stocco, Orsini, Sirtori e Ardito, who shoot 100 shots per piece against enemy lines between Revedoli and Caorle; the 20 November is the turn of the opposing positions at Grisolera. This target is again attacked by the 23, this time by 8 well destroyer. The enemy reaction, entrusted to coastal batteries and aircraft, proves to be ineffective.
To add, as the British say, insult to injury, the 25 November gunboats Captain Sauro e thunderbolt - two small former Habsburg merchantmen captured in the 1915 - they even date the Piave for 5 kilometers, cannonading and strafing all the Austrian landmarks sighted one by one.
For its part, the Austro-Hungarian navy, in order to support the advance of its Army from the sea, had transferred the battleships to Trieste Vienna e Budapest. These battleships are both damaged in the November 16, in front of Cortellazzo, from the precise 152 mm coastal battery shot commanded by the vessel lieutenant Bruno Bordigioni; although forced to withdraw from the subsequent intervention of the Italian naval units, they still continue to represent, to all effects, a constant potential threat to the Italian sea front on the Piave.
The night between 9 and 10 December 1917 i MAS 9 (commander the vessel lieutenant Luigi Rizzo, creator since the spring of that long-studied venture) and 13 (chief helmsman 1 ^ cl. Andrea Ferrarini) set sail from Venice, under the escort of the torpedo boats 9PN and 11PN. After almost two hours of hard and silent cutting, by hand, of the obstruction cables, the two MAS penetrate into the Vallone di Muggia, sailing slowly and without noise on the electric motors. After a final reconnaissance, intended to confirm the lack of parasiluric nets in the port basin, the MAS launch at close range.
Il Vienna, hit in the middle of the ship, sinks in a few minutes. The opposing reaction does not prevent the small torpedoes from leaving that port and returning, unscathed, to the base.
The sinking of this battleship is the first great Italian success on the sea of the Great War, achieved after years of tenacious efforts. The action, well planned, is cleverly communicated and valorised in such a way as to underline the trend inversion of the nation after almost two months of crisis.
Creator and convinced supporter, since the 1915, of the strategy of the "battle in port" is Admiral Paolo Thaon di Revel, Chief of Staff of the Navy in the 1915 and again in the 1917-1919. The future is always at the forefront Grand Admiral it proves to be constantly open to new ideas, from naval aviation to submarines to MAS and armed trains, and encourages the initiative of its own sailors, not hesitating to personally verify the "scene" of forcing the opposing ports, such as when a September night 1917, goes aboard a motorboat a few hundred meters from the Trieste obstructions during the final drafting of Rizzo's plan.