One weird thing about what I'll politely call anti-immigrant crackpottery is that their side lost. In the early 90s, in much of the country, newly arriving immigrants, especially ones perceived as being of a different race, were truly a new thing. % and total foreign born declined for decades, before trending back upwards in the 70s, and the new wave of immigrants were initially pretty geographically concentrated. Some states had them, but most didn't. So while I don't approve, the "we must stop this thing from happening" position made sense. For most locations, it hadn't happened yet.
But now, you know, they're everywhere.