The cost of labor is not what drives business overseas. That is a big fallacy. Exception is items like shoes, garments that are labor intensive, Regs, insurances, G&A is the savings. Also less capital intensive to buy from a mfgr than commit to equipment. Unions don’t play the role in exporting jobs that you think they do.
Can you explain then why the Japanese don’t like union shops in the US? My bro worked for Kawasaki and they would rather close the plant than allow a union in.
Labor cost is the area where companies are the most flexible. It’s easier to cut workers to reduce costs than get rid of a major piece of equipment.