When British airline authorities imposed harsh new restrictions on carry-on baggage in response to a terrorist threat, few complained. But when officials began murmuring that the near-ban on hand baggage could become permanent, musicians cried foul. “The impact if these policies continue will, over time, be inconceivable. London, along with New York, is one of the musical capitals of the world but these restrictions could lead to the erosion of that status — and of the reputation of Britain as a whole — as musicians are forced to alter their plans.”