These problems can be mastered. For example, the Palestinian nationalist cause is also a "big tent'' with many feuding factions, but all have given their assent, for many years now, to being represented by Yasser Arafat in peace talks with the Israelis.
Anyone who points to anything done by the Palestinians as an example of a successful model we should follow is a fool.
Of course, if Yasser Arafat genuinely wanted peace with the Israelis, there'd be peace right now. The trouble is, these people (terrorists) use negotiation merely as a means to distract their perceived enemy while building up a position of strength from which to attack.