The song brings to my mind a German warfilm I once saw. It was about the crew of a German submarine on the Atlantic in the 2nd WW. After having destroyed several enemy ships their vessel was hit and damaged so they couldn't get back home, they were "cast away on the water". All they could do was either surrender to the enemy or hide deep down waiting for death. I don't remember how the film ended, if they actually drowned. In the song the soldier is either dreaming when he's sleeping in his cold bunk in the trapped, "drowned" ship, in the "vault", or at the moment of death he sees his life as a series of flashes. One flash is a peaceful image of the submarine at the start of their journey, smoothly gliding through the sunlit water just below the surface. Another is a horrified glimpse at the devastation their torpedoes caused, "the slaughter". But more than anything his last thought, or his dream, is about his little fair-haired daughter to whom he reaches from his "grave". If this is what the song is about, I'm once again dazzled by Mark's skill in expressing so much with so few words!