WARSAW, Poland – Holding out Poland's transformation to democracy as a model for the world, President Barack Obama on Saturday exhorted Western allies and the American public alike to extend their support, energy and vision to those now reaching for democracy in the Middle East and North Africa. Obama wound up his six-day trip to Europe with a message aimed squarely at the people of the United States, saying that in a time of tight budgets, "I want the American people to understand we've got to leave room for us to continue our tradition of providing leadership when it comes...