I Agree That "Illegal Alien" Is Not A Pejorative

Since "alien" does indeed mean "foreigner" or "not belonging", "alien" is not a pejorative. In fact, Tanakh uses "alien" several times. For example:

1. Deuteronomy 14:21 (Torah)
   “You shall not eat anything that dies of itself; you may give it to the alien who is within your gates, that he may eat it, or you may sell it to a foreigner; for you are a holy people to the LORD your God. “You shall not boil a young goat in its mother’s milk.
   
2. Deuteronomy 23:7
   “You shall not abhor an Edomite, for he is your brother. You shall not abhor an Egyptian, because you were an alien in his land.

3. Ephesians 2:11-13 (Hadashah)

   ¹¹ Therefore remember that you, once Gentiles in the flesh—who are called Uncircumcision by what is called the Circumcision made in the flesh by hands— ¹² that at that time you were without Christ, being aliens from the commonwealth of Israel and strangers from the covenants of promise, having no hope and without God in the world. ¹³ But now in Christ Jesus you who once were far off have been brought near by the blood of Christ.

Also, documents— including draft cards— used the term "alien" in the 1900s. For example:

"Alien, Declared [For Naturalization]"