Citizens in three American states have voted to prevent traditional marriage from being redefined, reports John Elsegood.The greatest threat to marriage and family is the attempt to legalise same-sex marriage, according to Lynn Wardle, law professor from Brigham Young University in Utah. He warned the October national conference of the Australian Family Association in the port city of Fremantle, Western Australia, that marriage was a national treasure and the most important of social instit…