Do I say “migrant workers” or “foreign workers”? What’s the difference?

[This question came up in a chat group I’m in. My response below.]

Let’s think about how the words “migrant” and “foreign” are used.

When I am dealing with an idea that is completely unfamiliar, I say that “the idea is foreign to me”. When an object that does not belong in a human body enters it — like a sharp piece of something — we say something like “the foreign object entered his body, causing injury”.

When we think of “migrants”, on the other hand, we think of migrant birds, migrant animals — or the fact that the vast majority of us (Singaporeans) are either descendants of people who migrated from lands some distance away or first-generation migrants.

Describing people as “foreign workers”, therefore, foregrounds the differences between “us” and “them” — they are foreign, they are alien, they are something other than us.

But when we say “migrant workers”, we leave more linguistic space to acknowledge commonalities. They are migrants, and we are migrants and the children of migrants.