David Edgar says political theatre will never disappear. “For most of the 30 years in which I have been doing political theatre, it has been on its last legs. Over those years, I have spent more time than I care to consider sitting on panels in black-box theatres discussing whether this much-contested genre has any future. In fact, as I argue roundly on such occasions, the anatomising of contemporary society has been the great project of British theatre-writing since 1956, and whenever one wave seemed spent, another arrived to take its place.”