Everyone agrees that certain sectors of society—energy, telecommunications, water supply—are critical infrastructures. But what about monuments and icons? Key industry buildings? Sports stadiums and other large gathering places? More and more sectors are being included under the rubric of critical infrastructure, according to a review of presidential orders and directives, federal statutes, and government reports. The various documents mentioned here are on SM Online. (critical infrastructure [1], terrorism and national security, physical strategy, national strategy  )