The sudden descent into what Pakistan's defence minister has called 'open war' with neighbouring Afghanistan represents one of the most serious escalations in relations between the two countries in years.
For years, tensions along the long and rugged Durand Line border have simmered, characterised by intermittent clashes, militant attacks, and fragile truces. But the latest round of hostilities, headed by Pakistani airstrikes on Afghan territory and retaliatory strikes by Afghan forces, has shattered that uneasy calm and caused chaos through South Asia.
