Shiraz Ahmed was tending his music store in Islamabad, the capital of Pakistan, when a group of 15 bearded young men walked in bearing bamboo poles and a chilling message. Politely but firmly, they instructed him to take down the colourful array of Bollywood and bhangradance tunes on display and to restrict his business to Islamic music. “They told me I had to change my business,” said Mr Ahmed, 25, whose family has run the store for 15 years. “I am so confused. I don’t know what to do.” Until last week he might not have worried about these men...