You sir are an ass.
Thomas,
Most people in any of the World's navies do their watch and go home/bunk. I very much doubt if any officer or enlisted are looking for 'adventure' aside from the shore-leave type, avoiding either local police or MPs, and local criminals also.
On duty, most navy people expect predictable SOP behaviour. In fact, that is the training.
SEALs require a somewhat different personality dictated by the nature of their expected operating environment and mission profiles.
Marines are likewise attracted to their service for entirely different reasons to those the sailors have in choosing the naval service.
It seems to me that the PCs aim should be stated before the adventure in such a way that would suggest they will, or at least should try to, survive the adventure. At a guess the most 'adventurous' of people in this world are high stakes bank robbers. Even these expect to get away with proceeds of crime to retire somewhere with a false identity.
IMHO it is not a mark of a good GM who continuously exposes, or allows PCs to expose themselves to, hair's-breadth-away-from-death experiences. Even war is "Months of boredom punctuated by moments of terror." (November 1914) I think though that many GMs run their adventures like a sit-com, where something MUST be happening all the time because they MUST hold the audience's attention to get the ratings before the news comes on. I think much of the adventure should be boring and mundane. Even spies in warzones do not sweat adrenaline 24/7.
Most people here will probably disagree
Greg