Sir Roy Strong is the man who made museums fashionable. In his own words, “a young man from nowhere, who went somewhere!” – exploding a post-war world of privilege and cultural snootiness to put art at the heart of London’s swinging sixties. After his time at the National Portrait Gallery and the V&A, nothing would ever quite be the same again. Yet now, Sir Roy is an ardent critic of falling cultural standards in Britain. On the eve of his 80th birthday, he looks back with pride at his genius for popularising the arts and ponders the question – was it all his fault?