WAS it Diwali last Thursday? You could have fooled me. A classical October afternoon, silken sun, blossoming trees, not a sound on the horizon. In the evening, lights on balconies, and yes, a few hours of pataka fire, but swiftly, silence again. Thanks to a high court order, campaigns by the National Foundation of India (NFI), the Central Pollution Control Board (CPCB) and the raised collective conscience of several hundred schoolchildren, the pataka is, at last, politically incorrect.