An establishment sex scandal involving powerful men, young women and a high-society fixer, which erodes public trust and ultimately brings down a government… the echoes of 1963 should send shivers through this Labour administration, says Anne McElvoy R ight now, Peter Mandelson is holed up in the Wiltshire estate in a cottage on the land of a wealthy friend, his political, diplomatic and business careers in tatters, shunned by those who long courted his company and advice as an acerbic wit and