For instance, if you believe the border should be strict to keep out serial killers, what does that have to do with removing Korean car factory workers who aren't serial killers?
It sounds like you're saying that you want the country to have open borders so that everyone can come live and work here given they pass some basic checks (no criminal history for example). I am not saying that is wrong, but that's not how pretty much every country in the world operates.
Why?
> A company shouldn't even hire anyone who is not eligible to work legally in the country.
Apart from the legal punishments themselves, why not? What goal is achieved by this?
Regardless, the culture is that of a nation of immigrants. I don't see how anything here can cause major cultural shift away from that. I am willing to bet you won't be willing to elaborate either, so next goal post move please...
Also the US and Western European countries are in much better economic and civic conditions that the immigrants can take advantage of to live better lives and contribute.
Once they are in (incl illegally so) you concede you have lost on this instance. Now you admit that forcefully removing immigrants carries too high a cost (literally + damage in the communities you remove the immigrants from + your humanitarian image). So you don't.
Somehow that balance seems really hard to get right and edge cases (criminal record) matter.