Is there a cognitive bias which describes expert communities' overestimation of their potential impact? I was recently trying to argue that the Democratic National Committee's efforts to undermine the Bernie Sanders campaign were probably ineffective, and that those who attempted to do so probably suffered from a specific cognitive bias. Namely, due to their presence in the "political operative" nexus, they tended to overestimate, in general, the impact that political operations have on elections, swaying public opinion, etc. 

I wonder whether social scientists have observed that, in general, experts overestimate their ability to make an impact, because they put the system they belong to on a pedestal. Has such a cognitive bias ever been discussed in the literature? Is there a name for it?
This sounds like a mix of biases "due to the effectiveness of a search set", "the illusion of validity" and "biases of imaginability". See judgement under uncertainty [Science, New Series, Vol. 185, No. 4157. (Sep. 27, 1974), pp. 1124-1131.].