You can't simply expect everyone in every faction to handle diplomacy/diplomatic relations in the same way, nor is it fair to try and look at something from the outside and go "Omg omg those guys are so bad at diplomacy", when you may or may not have the whole context of a given situation.
My opinion (and a common piece of advice I've given to many people I run into around here), is that if you want to make a change in the diplomatic affairs of any particular faction or group, you should JOIN that group, and work at it from the inside, and see how things are -really- handled, instead of trying to look at something from the outside, and pass judgement on it without knowing all the right information.
That's my two cents, may or may not be relevant to the entire point of this thread, but I think that it is, so there you have it.