Antique pattern maker's vise - GIF

[Toolmaker51]

No US Armed Forces had training useful to industry exceeding that of the Navy; not everyone makes service a career.
Certainly demand for individual castings lessened with smaller fleet, but repairs are still conducted. Ability to prepare and pour metal at sea, combined with other functions like machining and welding in a mobile 'factory'; nothing short of astounding. There remain two active submarine repair vessels Emory Land and Frank Cable, unclear how long they'll remain.
My ambivalence to service isn't well founded, being a 26 year veteran. Disliked most rewarding aspects seemed to dissolve. Folks still inquire as to my rate, Quartermaster [Navigation], from shortly after draft 1972. "We thought you'd been a machinist." [aka Machinery Repairman, MR] Yes, I was machining already 4-5 years by '72, career of choice maybe 10 years before that.
Distilled into elements, Navigation and Machining are very much alike. Instead of calculating time-speed-distance, its metal removal rates. N-S/ E-W of a compass and altitude, the Cartesian representations X-Y-Z, including positive and negative numbers. Angular measurements like time and position of planets, the trigonometry of design. Chart corrections, red-lining blueprints. Submerged geographic features or territorial waters, I never ran us aground, caused an international incident; and never drilled into a vise or machine table. Planning, attention to detail, using instruments, befit either innumerable ways. I can stand back when discussions bat metric and inferial [lol M. Klotz] advantages to and fro, being subject to three- sometimes four- measurement systems at once.

"So we are now more confused, why not MR then?"
Because that, I already know how to do.
As a reservist, they had records of our civilian employment. Many weekends, and a few two-week active duty periods, with MR's spread thin, guess who got called?