My brother is a commercial crab fisherman in northern BC and Alaska. He serves the public by providing them food, and his occupation is far more dangerous than any of those listed above. My father is a steel fabricator, working primarily on vital ferries, naval and coast guard vessels. He is far more likely to die on the job than any of the men who serve on those ships, and they couldn't operate without him.
I think it odd that the uniformed services make this artificial distinction between their "public service" and those who labour in dangerous jobs in the private sector or non-uniformed public sector positions. Some argue that the difference comes from their conscious decision to serve, but based on my personal experiences living in a military town, most who serve do so for a paycheck, just like those who hold equally (or perhaps more) vital jobs that don't come with a spiffy hat.