This is an extremely good essay; my only criticism of it would be that the conclusion ("shooting a cop is not a particularly effective tactic and will probably get you arrested or killed") is too self-evident to warrant this much analysis, but it turns out that's not true.
Liberal Currents"The material action—shooting a cop—combined with the aesthetics (vandalism, graffiti, disorder, guys in ski masks…)—together meant that it was easy for the government to paint them as terrorists, and difficult for them to present themselves to a mass audience as sympathetic protesters."