I have no problem with cliques by way of freedom of association. But we have tried running society through cliques, and in all cases, what you end up with are variations of the mafia or worse.

Modern colleges, startup incubators, professional associations are some examples of cliques that are better than mafia. I guess a key is that these cliques do not completely encompass every aspect of a member's life and do not use violence as a means to enforce their rules.