Nothing like now. This is a great wound to America.
To the US? No, the peak immigration to the US from non-English speaking backgrounds was probably in the 1890s to 1910 CE or so. We had massive immigration, due to various factors. We coped, the public schools in the big cities in the Northeast - where the population tended to come in - did yeoman duty in helping to teach & acculturate the children, & there was also adult education - mostly language lessons, as I recall.
By what metrics do you consider that worse than today?
It's numerical - by sheer weight of numbers. Was there some other metric to apply? It seemed like a straightforward comparison to me.
So because we had a big wave before and managed to deal with it, you assume that we can again.
That's assume that the immigrants are basically the same and the nation is basically the same.
Both are not true.
The various European colonies & then the US in the New World have had a series of waves of immigration, typically from disasters or wars or crop failures in Europe. The Irish, bless them, were Caucasian & Christian & spoke English (often enough). It didn't help them in the short term, because groups of people & governments & churches can improvise - the Irish weren't the right flavor of Christianity (even if they were of the first flavor, excepting Judaism), they didn't come with scads of money nor aristos to speak up for them. & they were accused of being illiterate, thieves, drunkards, undisciplined, too fertile, & so on - the usual litany - as if that were going to deter anyone.
Yah, I assume that the US is still attractive - politically, economically, religiously, technologically, & in other ways - to a lot of the World. People still want to come to the US, & throw in with us. Yes, we managed to bring in peoples from Eastern & Southern Europe - & still the republic soldiers on. We've brought people in from our various adventures in Asia, the Middle East, Central & S. America, Africa, the Pacific - & we're still standing.
Yes, we have problems. But I don't see people braving mines, guard dogs & automatic weapons fire to break into N. Korea, China nor CIS - nor Cuba, for that matter. As long as people vote with their feet & against the odds & dangers to come here, I figure we're doing something right.