A shaky grip on the western front

Government tents, housing hundreds of Pakistani families displaced by the violence between militant groups and the army, in Khar in the Bajaur district of Pakistan, at the border with Afghanistan. — Asim Hafeez/The New York Times

IN the rugged mountains of Pakistan, the resurgent Pakistani Taliban are waging a relentless and deadly guerilla war against Pakistani security forces, in the biggest terrorism threat the South Asian nation has faced in a dozen years.

Pakistan has responded to the insurgency, which was nearly defunct just four years ago, with drone strikes and what it has called targeted operations.