Illegal ALIEN invasion.
Immigrants are people who apply to be immigrants, wait their turn, pay their fees, learn the language and comply with the laws.
Illegal aliens don’t.
Lurkin, you beat me to it. It is very important that we don’t let the left win the war of words. Words mean something and there is a whole lot of positive implications in the word “immigrant” that do not belong with these people. “Alien” is precisely what they are.
“Illegal ALIEN invasion.”
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I’d go with “the attack on America by foreign criminals”. Kinda wordy, but accurate