India, July 14 -- The debate over citizenship and proof of it has grown louder in recent days, powered by anxieties over the ongoing Special Intensive Revision of electoral rolls, and a technically accurate clarification by the external affairs ministry that the passport is a travel document, and nothing more. Retired judges have further muddied the already unclear waters by giving lengthy interviews on what should be, rather than focusing on what is. The government's position on this is clear (up to a point) and has been articulated repeatedly in Parliament: Citizenship is defined by the Citizenship Act. This is helpful because it clarifies what does not constitute proof of citizenship: Aadhaar numbers (which were never meant to); passpo...