Too lazy to look it up but IIRC a number of the inventors who developed the technology that boosted the US into the worlds most powerful economy were foreign born or the sons of immigrants. In the old days new people coming in were largely doing so in hopes of making it big in a free economy, not becoming dependents of a generous welfare state.

That's true, it is online. But those kind of things are all that I came up. Food someone else mentioned. The reality is that a homogenous cultural milieu such as Japan's or previously nordic countries lent itself to national goals and cultural tradition.