British Prime Minister Tony Blair wrapped up a Middle East tour Wednesday with a blunt speech warning that the world faces a monumental struggle between moderates and extremists — and labeling Iran the main obstacle to hopes for peace. In an address to business leaders and journalists in Dubai, Blair said combating extremism and the violence it foments was the greatest challenge of the 21st century. He said the lesson he had drawn from his five-day Mideast trip was “startlingly real, clear and menacing.” Full Story