What a triumph of entrepreneurial empire-building — if that’s still an acceptable phrase — is the £6.8 billion acquisition of the Asda supermarket chain by Blackburn-born self-made billionaires Mohsin and Zuber Issa. Sons of Gujarati immigrants, these brothers have advanced from a single petrol station in Bury to a chain of almost 6,000 in ten countries with convenience stores and coffee shops attached.