Pakistan, Feb. 8 -- The suicide bombing at Islamabad's Imambargah Khadijah-tul-Kubra was meant to signal reach, to suggest that even the federal capital lies within a militant firing line. Fortunately, the response that followed did everything possible to restore order and mitigate the chaos. Instead of confining itself to the crime scene or the ritual language of condemnation, the state moved quickly to dismantle the infrastructure that made the attack possible, treating it as a well-entrenched operation rather than an isolated eruption of violence.

Coordinated raids across the length and breadth of the country led to multiple arrests, the elimination of a key facilitator in Nowshera, and the detention of the bomber's close relatives fr...