Actually it does have something to say about political ideology, from the perspective of the poster, anyways.
The obvious assumption regarding the graph provided would be that the higher educated individuals would be Liberals, and that they far outnumber the lesser educated Conservatives when asked if political violence was justified.
Of course agreeing with something and actually doing it are two different beasties. The more highly educated tend to be less inclined when it comes to doing anything that they may get scuffed up doing in the process.
Conversely, the lesser educated may prove to be more prone to jump at the chance to become cannon father.