The Dissenting Voice at the Tower

The order in which Shem, Ham, and Yafet are listed throughout Parshat Noach. After listing the descendants of Yefet, Ham, then Shem, the story of Migdal Bavel appears after which it goes back to Shem. Why does the story of Migdal Bavel interrupt the Shem genealogy, is meant to be seen as part of the Shem genealogy narrative?

The generation of the flood was one of havoc and disunity whereas the generation of the dispersion was one of unity. How did the latter deal with dissonance?