LEGAL immigration, i.e., done in a formal and orderly manner, examining the credentials and history of the applicant, limiting the size of the flow coming in, and assuring that the applicant has every intention of becoming a good and useful addition to the loyal citizens already living in the country, no problem.
It is the multitude of cat burglars, thieves, liars and transients who have no good will toward the country they enter, that are the problem. And almost nothing is known about them until AFTER they have committed some grievous felony, there has been great economic and/or personal harm done to innocents, or other egregious misbehavior has been visited upon unsuspecting folks. And this is generally designated as ILLEGAL immigration. The illegal part does not stop with just the nefarious means of entry.
Spend 6 minutes watching Roy Beck DEMOLISH the entire immigration fraud scheme:
https://www.youtube.com/watch?v=LPjzfGChGlE
“there has been great economic and/or personal harm done to innocents, or other egregious misbehavior has been visited upon unsuspecting folks.”
On target. The pig politicians and the Nazi media care more about alien invader rapists and murderers than American citizens.