Spring of the 1918, the fate of the Italian war is poised. After two years of frontal attacks, the Austrians have called the Germans to their aid: the defeat of Caporetto and the Italian defensive successes of the Piave and Monte Grappa have been followed in order. Now the situation is deadlocked.
The 1 March 1918 young Admiral Horthy took command of the Austro-Hungarian Imperial-Royal Navy.
The chief of staff of our Navy, Admiral Paolo Thaon of Revel, knowing the mentality and the precedents of the adversary, follows this appointment with great interest, judging as probable and imminent a change of attitude and foreseeing that the usual prudence of the enemy will probably follow a header. The reason is clear: Vienna is hungry, worse than Berlin. Russia has surrendered, but there is no way to bring its grain and its oil beyond the Danube, due to the control of the Mediterranean exercised by Italy and its allies. As for the morale of the Habsburg sailors, he is under his heels.
The Austrians thus plan a spectacular raid against the mobile barrier device of the Otranto channel, put in place by the Italian Navy with the collaboration of the Anglo-Frenchmen from the beginning of the war. The Hapsburgs expect to be able to surprise the Italians, obtaining a success to be resold, as propaganda, as a second Lissa. We are on the eve of the offensive on the Piave, and in the intent of the enemy an Italian naval defeat would have had serious moral consequences on the spirit of resistance of the whole country.
In the perspective of an enemy action, Admiral Thaon of Revel issues a synthetic dispatch, warning the Navy commands that the Austro-Hungarian line of conduct could be such as to expose "... to the imprudence of which we must be ready to take advantage ... we will take advantage of every enemy move to attack with submarines, destroyers, torpedo boats and MAS "
The evening of the 9 June 1918, the corvette captain Luigi Rizzo, already sinking, in December, of the Austrian battleship Vienna, receives the order to go out to sea with a section of MAS, the 15 and the 21. This is the "usual assignment: exploration, ambush and mine search". While the small Italian units move towards the patrolling area, unbeknownst to them the imperial fleet exited in force from the port of Pula, heading south. These are well 45 units, including all available battleships.
The 10 June 1918, MAS 15 and 21 are off the small Dalmatian island of Premuda. At 3.15 hours in the morning, the Italians spotted "... a big cloud of black smoke on the horizon". Not yet able to distinguish the type of ships, and by excluding that it could be of Italian units, the Rizzo captain legitimately supposed to be an exploding destroyer of explorers. Without any hesitation, the Italian commander orders to prevent the threat from being hidden from the enemy ships, to attack them by surprise and to open their way back fighting.
Dawn, the little light in favor of the MAS, when Rizzo signals to Ensign Aonzo, commander of the other unit, to prepare himself for the attack. The two small torpedoes advance slowly, moving against those that they consider a group of torpedo boats in exploration when, shortening the distances, they realize that they are in the presence of the Austrian naval battle team.
The sea is calm - perfect calm - limited visibility by a slight haze: a unique situation, a "prey" indispensable for the MAS Ace with the taste of hunting, which without hesitation and with clear awareness of the evident disproportion of the forces in field, however, challenge the two battleships escorted by ten units that protect them from all sides. A few words in a low voice (at dawn every sound runs away) between the two units, and the engines slowly increase the number of turns. No "mustache" on the prow. The petrol engines seize without problems. The Italians thus pass between two escort torpedo boats without being seen, thanks to a good kinematics and great seafaring expertise. We are in the launch circle. Out! The torpedoes descend into the water, the angle is perfect, from manual. The estimated distance of about 300 meters. 03.31 hours, "Torpedoes hit, target hit!". As reported by the commander of the Tegetthoff: "It was observed on the straight of the St. Stephen a flash of light accompanied by the thunder of an explosion ". Rizzo's MAS 15 hit the battleship St. Stephen, while the MAS 21 launches its torpedoes towards the Tegetthoff, which will only be saved for a malfunction of the burst of a torpedo, which strikes it without exploding.
Quick approach and route of removal! But now the two MAS are chased by a fighter that shoots on them, surprisingly Rizzo uses the only weapon still available on his MAS 15 to stop the enemy unit from pursuit, which is an anti-submarine bomb that explodes ahead of the hunting causes these to renounce by reversing the route.
While the St. Stephen, dying, sinks, the victorious MAS 15 and 21 re-enter the port of Ancona. The Monte Cappuccini Semaphore, barely sighted, saw the great flags hoisted on the MAS and saw the victory and gave the news to the Ancona Marine Command with the famous telegram, vibrant with enthusiasm: "Miles 15 N-NE, two motorboats discharged with torpedoes but laden with honor and glory direct into port".
The action of Premuda, for its military and political consequences, is tantamount to a great battle won, which definitively changes the course of the First World War in favor of Italy and gives great prestige to the Navy that, from the 1939 onwards, in memory of that event, celebrates its Day the 10 June. In recognition of the heroism shown in action, the commander Luigi Rizzo "of Premuda" is proposed for a second gold medal for military valor, after the one already paid for the sinking of the battleship Vienna. It is an unprecedented fact. Moreover, they point out to the court, that officer is of republican sentiments. "The composer Mario, who wrote the song of the Piave, is also. Good patriots ā, replied Vittorio Emanuele III signing, serenely, the decree.