airport security:Miami Dade Police officer Mark Huetter walks the concourse at Miami International Airport.:McClatchy Tribune

Miami Dade Police officer Mark Huetter walks the concourse, Thursday, August 10, 2006, at Miami International Airport. The U.S. government raised its threat warning to the highest level for commercial flights from Britain to the United States in response to a terror plot disrupted in London. (Mike Stocker/South Florida Sun-Sentinel/MCT)