What criteria are you using for socially mobile? I agree that welfare, the way it's designed in the US, is a trap. I don't think you will find vast quantities moving out of poverty in the US, because there is no incentive to do so. Democrats crafted one of the most suffocating welfare systems in the western world. It penalizes people for working and getting married. As to other forms of social mobility, I don't imagine we have a large amount of people moving up from middle class, because it's a statistical anomaly. Middle class is the standard, with the really rich being rarities, so it wouldn't surprise me if those numbers don't change as a percentage. Generational wealth is not commonplace in the US. I'm sure some families manage to stay on top, but it's a revolving door for the most part.

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