The Panama Canal's Miraflores Locks.

Panama, the U.S., and Chile have been conducting joint patrols in the Canal Zone, which some observers say could be a prime target for terrorism.

Hernan Arauz, a leading authority on the Dariin, said, "Terrorism is already a part of life in the Dariin. ... Securing the canal is no different than securing the Dariin. Both areas are central to our national identity."