I don't talk much about work with my wife. Mostly I can, but why would I want to take my work life home. I spend hours talking about work stuff at work. Let's talk about other stuff at home.

Perhaps it's different when your job defines you as a person or your job is your life.

It helps to live in a place where most people do work like this. It's more culturally acceptable to simply not ask in the first place.

I'd go as far as to say that it's so ingrained in some folks, that it's a dead giveaway what they're up to based on whether or not they ask you what you do for a living.

I was in the Air Force with a secret clearance, working on radar systems. There's some stuff i can't talk about for legal reasons, then there's stuff i don't talk about because it would make me look dumb. Like that time i worked on the circuit breaker panel without cutting input power. Or that time we forgot to open the vents before powering up the thing.