ow does Gladwell establish the similarities between Roseto Valfortore, Italy, and the region the Rosetans settle in the United States?

Gladwell discusses the way the Rosetan's transported the paesani culture of southern Italy to the hills of eastern Pennsylvania. He notes the way they'd created a powerful, protective social structure that serves to insulate them from the pressures of the modern world.

What Wolf began to realize was that the secret of Roseto wasn't diet or exercise or genes or location. It had to be Roseto itself. As Bruhn and Wolf walked around the town, they figured out why. They looked at how the Rosetans visited one another, stopping to chat in Italian on the street, say, or cooking for one another in their backyards. They learned about the extended family clans that underlay the town's social structure. They saw how many homes had three generations living under one roof, and how much respect grandparents commanded. They went to mass at Our Lady of Mount Carmel and saw the unifying and calming effect of the church. They counted twenty-two separate civic organizations in a town of just under two thousand people. They picked up on the particular egalitarian ethos of the community, which discouraged the wealthy from flaunting their success and helped the unsuccessful obscure their failures.