Twenty years ago, novelist Salman Rushdie was a wanted man with a million pound bounty on his head. His novel, The Satanic Verses, had sparked riots across the Muslim world. The ailing religious leader of Iran, the Ayatollah Khomeini, had invoked a little-known religious opinion - a fatwa - and effectively sentenced Rushdie to death. Never before had a novel created an international diplomatic crisis on such a scale, and never before had a foreign Government publicly called for the killing of a private citizen of another country.