I’ve come to the conclusion all these years later that it was some combination of shared hardship, forced closeness, security in employment, and a core belief that we were all working toward the same goal. We were in it together, and it felt like it.
This seems to explain why people who work in restaurants can often be close. There’s the shared hardship of dealing with a dinner rush, there’s a lot of forced closeness in the kitchen, and everybody’s working towards the same goal, whether that’s just getting through the shift, or trying to produce a really amazing dining experience.
There’s probably another one: depending on other people who work right next to you. If you’re working alongside other people but everybody’s working on their own project it’s going to be different than if you depend directly on the person next to you for whatever you’re doing.
Maybe it just comes down to people not being committed to their work
I think it’s the lack of all the things you mentioned. At an office job the hardship is pretty mild other than occasional “crunch time”. There’s some forced closeness, especially when people are crammed into an open-style office. But, I don’t think that’s the same kind of closeness you get in kitchen, or on a ship, or in a factory. You may be working towards the same goal, but it’s often a nebulous and distant goal. And, often, the goal isn’t something that feels particularly meaningful. You’re helping ship a product that may or may not be vaguely useful to some customers you’ll probably never meet.
But, I think the big thing is the lack of security. In the military you literally can’t leave, and unless you do something insane you’re not going to get fired. At most jobs, it’s extremely easy to leave, and many people feel like they’re always on the edge of being fired or laid off.