The Global Positioning System helps power everything from in-car satnavs and smart bombs to bank security and flight control, but its founder has warned that it is more vulnerable to sabotage or disruption than ever before – and politicians and security chiefs are ignoring the risk. Impairment of the system by hostile foreign governments, cyber criminals – or even regular citizens – has become “a matter of national security”, according to Colonel Bradford Parkinson, who is hailed as the architect of modern navigation. “If we don’t watch out and we aren’t prepared,” then countries could be denied everything from ‘navigation’...