Taliban school massacre: At least 140 dead in Peshawar assault (part 2)

At least 141 pupils and teachers have been killed after the Pakistani Taliban stormed an army-run school in Peshawar. The attack - the worst of its kind in years - is said to be retribution for the Pakistani military's months-long offensive in north-eastern tribal areas. How successful is the military campaign? And how should authorities deal with the Taliban - both in Pakistan and across the border in Afghanistan?