I used to build factories. We'd design and install the robots and machines of the assembly line. Final install took months. We never got work visas in those countries. We'd just say we were there for engineering meetings. Which we did have, but mainly we were installing, calibrating, and testing the machines we designed. I wonder if it's something like that. We did however hire local subcontractor labor for the generic work. If we sent 300 Americans over I suspect it might have set off some alarms.
You weren't necessarily acting unlawfully, and neither were the Koreans. From reports, they seemed to mostly have an ESTA or B-1 visa. This doesn't allow "work", but it does allow many business activities. For example:
> A B-1 visa may be granted to specialized workers going to the United States to install, service, or repair commercial or industrial equipment or machinery purchased from a company outside of the United States, or to train U.S. workers to perform such services.
Most other countries have similar policies. The line between those permitted activities and "work" is notoriously blurry. This often results in unexpectedly denied visas, and sometimes results in nasty letters or fines. It almost never results in this kind of show of physical force, even in unfree countries.
The BBC said they were all subcontractors and as you suggest, mechanics involved in setting up the factory in some way. Seems like it's exactly that, a contract house not wanting to go through the process of getting proper visas and getting folks in in any way.
As with a lot of things, I'm not so opposed to enforcing visa rules for something like this but maybe the shackles and method of detention weren't all that necessary. Also worth looking at fixing the reasons why companies are skipping the proper visa process, because nobody at all should be (or is?) opposed to LG/Hyundai setting up a factory in the US. Things we should be doing with a helping hand are being done with guns drawn instead.
But we all know they're doing it this way for the populist theater, there's folks out there that want to watch fascist police state theater on the evening news.
