Plot: What is a nation? From Corsica to Kashmir, from Quebec to Bosnia, violent separatist movements are fighting to form their own nation states. This edition of Arena explores the fabric of national identity, and follows four of the world's leading commentators on the subject - Eric Hobsbawm, Eqbal Ahmad, Desmond Tutu and Maxine Hong Kingston - as each embarks on a personal investigation into the different stories their nations told them