mdd: “The previous wave Jews were mostly irrevocably lost.”
I think that’s unfair to those immigrants who did manage to keep their faith. And they existed- I’m a proud descendant of one.
The thing is, it may even be true, what you’re saying, except:
1) If those same Jews had come over earlier (which I think is the point of zahavasdad’s posts) then arguably the US Jewish community would have just been revitalized earlier, and
2) The conditions, weirdly enough, of the 30s and 40s were better for observant Jews than those of the previous decades. The five day work week first became standard in the late 20s, and the Fair Labor Standards Act wasn’t made law until 1938. In fact, according to Wikipedia (no, I usually don’t quote Wikipedia but I found this interesting, and feel free to take it with a grain of salt), “the first five-day work week in America was instituted by a New England cotton mill to afford Jewish workers the ability to adhere to their own religious Sabbath.” It was early on, but until Ford instituted it in 1926 it was an anomaly.
Those frummer Jews really just came at an opportune time for Yiddishkeit.