I know “Made in the USA” has some legal implications, and common law evolves based on previous cases that interpret a law, or the words, at any given time — so the legal definition can evolve over time just based on the judges doing the interpretation ... we see this in constitutional law frequently as different political leaning/influenced courts interpret and rule based on their liberal or conservative interpretation of the law. It’s not set in stone, but the safest thing to do from a profit standpoint is to avoid unnecessary risk.
You see other approaches to compromise, like “Assembled in USA” and “Manufactured in USA”, though manufactured might imply ever bolt was sourced material and made here too. Even in California you see great variation in application of similar laws. Here in Napa there is regulation stipulating that to use “Napa Valley” on the wine label appellation is only legal if the grapes are 75% sourced from Napa County vineyards! Only 75%, in a case where this can have a discernible impact in taste and quality or consistency (if you twist your nose and swish your glass in the “proper” way when tasting). Maybe Martin just needs to imprint it:
Made in USA*