The purpose of the NPHC is to create "unanimity of thought, action and mutual interest ". I don't this has happened and am not sure if it ever will. For some Greeks, their organization is their life and they are not willing to step outside of their (insert two colors here) box and work with other organizations to achieve a common goal.
I'm guessing that the reason that our orgs are so divided is because some were created in response or rejection to those that preceeded. How can you unify with something you don't agree with??
