Springtime on the Border: <b>Line Item:</b> (left) A US Border Patrol vehicle, seen from across the fence in Naco, Mexico, monitors a stretch of border in Arizona that has rapidly become the busiest in the Southwest.<b> Armchair Vigilantes:</b> (right) Volunteer Minutemen scope out movement along the border, prepared to call any action in to border patrolmen via cell phone. <small><i>Andy Isaacson</i></small>