Exclusive: Former archbishop of Canterbury [Lord Rowan Williams] says Britain is no longer a nation of believers, as Telegraph poll reveals Christians are reluctant to express their faith.Britain is now a “post Christian” country, the former archbishop of Canterbury has declared, as research suggests that the majority of Anglicans and Roman Catholics now feel afraid to express their beliefs.In an interview with The Telegraph, Lord Williams of Oystermouth says Britain is no longer “a nation of believers” and that a…