Being a committed part of something larger than oneself is a major step in personal development. It goes beyond self awareness and into self actualization and realization.
For most people the first time this happens is kids, but there are other epiphanies in people's lives that help them "find their niche".
I mostly agree with the point, but not entirely.
For example, I tend to view myself primarily as megaprogman (substituted for my real name of course). As megaprogman, I believe x, y, and z are the best thing for humanity, my country, my state, my community, my family, my church, or whatever other social group I happen to belong to. However, my primary self identification is still me. Ultimately, I decide on what is right and wrong for me and how I choose to interact with others and I don't particularly care if others like it or not (with the exception being that I tend to need people to react a certain way to get a job done), because I think its the best thing I have come up with so far and I am the one who has to answer for myself in the end. (This doesn't mean I am an asshole or anything, in fact, I am quite popular with a lot of people and tend to be a natural leader, even though I am an introvert. Primarily because of my kindness and the fact that I care about the people around me, but my kindness is ultimately my choice because it makes me happy to see other people being happy).
Another person may come along and say I am primarily a Christian, Muslim, Liberal, Conservative, Rotery Club Member, Shriner, LARP gamer, or whatever. Because my primary self identification is with whatever group, I tend to look to them for my views, internal moral constructs, vision, etc.
I see advantages and disadvantages to either approach and I don't wish to judge which one is better, because each approach has their own merits. However, I am curious where people lie.
Ultimately, I think the reason I am asking this question is that my son was diagnosed with Aspergers recently and I got to thinking about my own life and I display many of the same traits he does, however, I have studied people long enough to figure out how to interact with them. So I am curious to see how the rest of the world is, I guess to see if I am normal or not. (not that I want to be if I am not, I am quite happy with who I am).