All most all the Foreign car companies are building cars in the South, non union States. Union is only part of that equation. Cost is another.
When I retired from the USN in 2001, Denso Manufacturing offered me a Job as a Maintenance team leader. I was given my Choice of three Plants. Battle Creek MI, my home town. Maryville TN and Athens TN. Starting salary in Battle Creek was 65,000 a year, in TN either plant was 55,000 a year. I chose TN.
Why, it was lots less money. Housing was way less in TN because land or property was way less. Tax was way less, insurance was way less, vehicle registration was way less. So not only was it cheeper for me to live in TN. It was cheeper for Denso to buy the land, to build the building, to pay the people, to pay their insurance, to register their vehicles and the list goes on.
Example, my dad had a 01 Crew Cab dually, I had the exact same truck but different color. His tag was 225 a year and 1000 a year insurance. My tag was 24 a year and 450 a year of insurance. I bought a one acre lake lot on the TN river for 60K. That year my Uncle sold his 120 by 150 lake lot in my home town for 750,000.
I could have a better standard of living earning 10K less than in MI.
Our wages were very comparable to union plants in the area, same with the plants in MI.
GM came to visit us. The wanted to know how we could make spark plugs, paint AC/Delco on them, and sell them to GM for less than they could make them for. Our three plug lines had only 2 multi craft maintenance guys on each shift and 3 production workers. GM had an Electrician, a machinist, a mechanic, an instrument tech, a software tech, a welder, a pneumatic tech, and a Hydraulic tech. So 6 more maintenance people per shift. They had 14 production workers for our 3. All that extra labor adds up fast, but union rules, the electrician only does electrical an so on. Union line worker cant take out the trash and so on.
Or workers actually made more than the Union as no union dues. Same vacation, sick leave and health benefits.
I'm not Anti union as all 4 of my grandparents were union, most my cousins are union, my brother is Union steward.