When Archbishop of Canterbury Rowan Williams gives a blessing to Prince Charles and Camilla Parker Bowles at the Guildhall, Windsor, there will, no doubt, be smiles all round. But this royal marriage is both a potential powder keg for the Anglican Communion and a reminder of anti-Catholic legislation.Prince Charles’s announcement that he is to marry his lover Camilla Parker Bowles in a civil ceremony on April 8 brought relief to those struggling with the prospect of a future Supreme Governor of the Church of England and monarch in an unmarried relationship with a divorcée.Williams, who has been consistently opposed to...