Communities are based on people coming together with common need, common interest, common idology. When Jah smote the peoples building the Tower of Babel and people began speaking different languages, they grouped with others who spoke the same language (so goes the fable of how various languages were born in my JW upbringing).
The United States was "settled" by religious sects leaving Europe due to oppression. And within each physical community, the settlements were also bonded by their common religious belief structure.
Up until the last 30-50 years, communities were often headed by the local church. Entertainment, moral attitude, family gatherings, singles dating, etc., were dictated and even supplied by the church. The non-belief of the last 30-50 years has brought about a solo-ness of mind and a certain loneliness and solo-superiority attitude, especially here in the US outside of the bible belt.
Community is not a bad thing. When we belong to a community, we are less alone, feel less wierd, and are usually happier. Unless, like in JW, and other religious and non-religious groups, it's taken to fanatacism. Community in Faith is not a bad thing, either. It's common today in other non-religious areas, such as AA, PLO, Rotary Club, etc. When there is a common basis, it's kind of nice to go to another city, or part of the world and find "friends" and sameness when you're alone, even when it's in a different language you don't understand. I'm speaking of my AA experience when I traveled on business.
I think it's the fanatacism that is being criticized in this thread.