For too long, Pakistan’s military and intelligence service have played a cynical and dangerous double-game: accepting billions of dollars in American aid while also aiding the Taliban and other extremists who threaten the US, Afghanistan and Pakistan’s fragile democracy. Pakistan’s military chief, Gen. Ashfaq Parvez Kayani, has been under strong pressure from Washington and his own government to clean up the intelligence service. We hope his decision to appoint a new spy chief this week means that he has decided to finally put an end to that destructive game.

General Kayani has put his own loyalist, Lt Gen Ahmed Shuja Pasha, at the top of the intelligence service. The two men must root out tainted officials and make clear that it is no longer Pakistan’s policy to promote extremists of any stripe. They must also retrain agents and military forces in counterinsurgency warfare. Whether they are up to those tasks is unclear. If there is another incident like the Indian Embassy bombing, the buck now clearly stops at General Kayani’s desk. There’s no time to lose. The militants are fiercely holding their ground and using increasingly sophisticated tactics to attack Afghanistan. Last month’s bombing at Islamabad’s Marriott Hotel is a chilling sign of the extremists’ ability to directly threaten Pakistan.