Teleology,
A person who commits violence as a result of their ideological beliefs is radicalized.  I'm not sure how this is a controversial statement for you.  And I really have no idea why you have trouble acknowledging that the tolerant center is the glue that holds society together. That includes the center left and center right.  Radical outlying groups on the fringe are the ones who tend to resort to violence in order to overturn the status quo, that's just reality.  So, I feel no need to squirm about anything.