You're right about the trades but Americans can't see that when they drive by. What we see is closed down boarded up factories, so most Americans knew exactly what Trump was talking about. Dems refuse to give Trump credit for knowing how to connect with blue collar workers.
Boarded up factories are due to a single issue from two causes, for the most part:
OSHA
EPA
If you don't believe that, you're a fool. Those two agencies alone have become so pedantic, so overly meddlesome, it's insane. The CPSC is another agency run amok. They make it so expensive and difficult to do anything in manufacturing that it moves overseas.
Even the Navy was inclined to mostly paint ships at overseas ports and pay locals because the regulations in the US were so costly it was worth having it done elsewhere.
At one point in the Navy I wanted to install a sandblasting cabinet in my shop. The unit included a baghouse and filtration system making it very clean. The officers in charge said no initially, fearing issues with environmental things. I produced about a 6" thick pile of paper for NAVOSH (the Navy equivalent of OSHA) rules, and EPA regulations. On top of the pile was a letter I got from Bob Blaskiewicz, the then head of the Air Quality Division of the EPA out of Research Triangle N. Carolina, that said that the EPA didn't regulate sandblasting and that my set up sounded like a great way to do that work.
I got my cabinet, but it took me weeks of research and effort to make that happen. That all cost money and time I could have devoted to other issues.
I also had to have a bucket in the shop--with cover--for used dry cell batteries. I had to provide electrical tape that you had to cover one end of each battery with before depositing it in the bucket. There were printed instructions and such on the bucket as well. In years, we never emptied the bucket, barely put more than maybe a couple dozen batteries in it (we simply didn't use many), but by god, that bucket had to be there and in NAVOSH inspections they looked to make sure we had it.
That seems minor, but those things add up. It makes doing anything expensive and worth moving it elsewhere. It's another "Flypaper report." (Look that up)