First of all, I don't know why you keep bringing up qabiil whenever Federalism is mentioned.
You seem intent on conflating Federalism with 'qabiil', when since the dawn of mankind, people have lived with their own families and extended relatives, this is natural and thus most people will live in regions dominated by their own kind.
For instance, the Scandinavians moved to Minneapolis and till this day, that's where most Scandinavian Americans live. You have groups like the Amish, who still live in Pennsylvania hundreds of years latter.
The issue is not 'qabiil', it's preventing power-crazed lunatics from taking charge.