First of all, there wasn't vast heaps of " welfare ", until FDR. Their WAS the dole, and many previous immigrants were on it. Even into the late 1930's, many immigrants did NOT speak or read ( gasp ) English. There were NO bi-lingual classes, in public schools, until a few decades ago. OTOH, there were newspapers, threatres, and entire communities, for centuries, here, where absolutely NO English was spoken/ heard / read. This is NOT anything " new ".
If you doubt me, go do some research. Meanwhile, I'll help you out a wee bit and tell you that in the very early part of the 20th century, an Hungarian Benevolent Society, upon their 25th year anniversay, excoriated it's members, in Hungarian, German, and English ( the entire hardbound book, given away to those who attended the grand dinner and ball , was written in ALL three languages ! ), to learn and speak English. BTW, those immigrants and their sons and daughters voted REPUBLICAN, for the most part. How do I know ? Because I own that and it's sister book ( which was for the younger members / the Young Petofi Society ) ; I inhertided them both. :-)