Can a biscuit factory make a ventilator? Can a car plant? In yesterday’s Sunday Telegraph, the health secretary, Matt Hancock, announced that the government was launching ‘a call to arms for a drive to build the ventilators and other equipment the NHS will need ... We now need any manufacturers to transform their production lines to make ventilators. We cannot make too many. If you produce a ventilator, we will buy it. No number is too high.’