Location, location, location. Well, and skillset of course.
I would strongly recommend against it though. The pay is terrible. There was a strong push for a few years to get people into the trades, and there was a strong misrepresentation of what the opportunities are really like.
Keep in mind that government contracts are a race to the bottom. The contracts go to the lowest bidder and since materials, etc. are a given, employee pay has really suffered. Being a machinist is not the path to a middle class life anymore for most people.
Both actually. Employers are stingy with PPE and you're constantly surrounded by dust, fumes and potentially harmful chemicals. Keep in mind this wasn't some tiny shop that made fences, I was working on military prototypes and aerospace projects.
I switch to the industry during the Obama administration, but after 2016 people were feeling a little too comfortable with their misogeny and racism.
To final straw was my direct supervisor becoming more radicalized into the far right. Not a comfortable feeling when they guy you report too leaves a 9mm with hollow points on top of his toolbox every day. The guy hadn't read a book except for the bible in 20 years, got all his news from Facebook and Fox.
I was a full stack web dev and Linux sysadmin for about a decade. Switched to welding and machining - I wanted to make something tangible for a change. The work itself was awesome (legos for grownups) but the industry is fairly toxic IME.
Right now I'm working on getting back into IT (Network security).
I'm the sole IT tech for a small manufacturing facility - I was already part time and just got the request to reduce my hours even further for now. The local job market is already subpar here, so I'm definitely concerned about the months to come.