Much of the news media refuses to use the term "illegal alien", and saying things like "undocumented immigrant" instead.
Now I learn that ecologists use the terms "alien species" and "invasive species", with the main difference being that the latter term is used to imply harm.
And many ppl argue that illegal aliens are beneficial to the USA, because they supply cheap labor, drive down wages, and support Democrats. And they validate some silly poem about "wretched refuse" ppl.
So maybe we need a term like "invasive peoples" to convey harm. The main objection to illegal aliens is not that they are illegal or that they are alien; it is that they are intruders who are destroying the ecosystem. The term "wretched refuse", which seems popular among pro-immigration folks, seems too pejorative.