Decima MAS: Where to Strike After Alexandria?

Junio Valerio Borghese, corvette captain commanding the submarine Scirè and head of the Decima Flottiglia MAS underwater operations

, a 35-year-old corvette captain, commands the submarine and directs the underwater operations of the , the Italian navy's assault unit. On 19 December 1941, his divers, riding piloted torpedoes known as maiali, slipped into Alexandria harbour and placed their charges beneath two British battleships. The explosions settled and onto the bottom, crippling at a stroke the backbone of the Royal Navy in the eastern Mediterranean.

The raid cost him his six swimmers, taken prisoner, but it proved that a handful of men could match a squadron. At La Spezia, the high command presses Borghese to turn the feat into a sustained campaign. The obstacles are plain: every sortie of the near a defended port wears down a scarce submarine, nets, searchlights and patrols are thickening, and trained crews can be counted on one hand.

Borghese weighs what comes next. He can shift the effort to Gibraltar by setting up a clandestine assault base as close to the Rock as possible; try Alexandria again despite the now-maximum vigilance around the British anchorage; or loose his combat swimmers against Allied merchant convoys in open water, targets more scattered but less guarded.