Pakistan, Oct. 17 -- The federal government has imposed an emergency and governor's rule in Khyber Pakhtunkhwa (KP), its most security-sensitive province. No government takes such a decision lightly. Setting aside an elected provincial administration carries political costs and invites questions about motive. Yet the issue before the country is twofold: is the measure lawful, and were conditions grave enough to justify it? On the first question, the answer is clear, because the Constitution provides for exactly this situation. On the second, the security picture deserves careful attention.

Over the past two years, KP has absorbed the heaviest share of militant violence in the country. According to federal government briefings, attacks ha...