Treaties reformulating the principles controlling the defense and operation of the Panama Canal were signed on September 7, 1977, by General Torrijos of Panama and President Carter, and ratified by the United States Senate on March 16, 1978, and April 18, 1978. Treaty provisions are contained in three documents: The Panama Canal Treaty, The Treaty Concerning the Permanent Neutrality and Operation of the Panama Canal (Neutrality Treaty), and Protocol to the Treaty Concerning the Permanent Neutrality ind Operation of the Panama Canal (Protocol). By the terms of these agreements (jointly, the Canal Treaties), the United States retains primary responsibility for the defense of the Panama Canal until the year 2000; although full sovereignty over the Canal and Canal Zone is returned to Panama immediately, the United States and Panama agree to provide for permanent "neutrality' of the Canal. The Neutrality Treaty provides for accession by other interested states to the Protocol, by which signatories pledge adherence to the permanent regime of neutrality.

Three patterns are emerging in the ownership of cable television systems in the United States. First, ownership is concentrating in fewer and fewer hands. Second, cable systems are increasingly owned by companies that own other types of communications media, or own sources of programming material, or own firms that are actual or potential manufacturers of cable hardware. Third, ownership by non-profit educational, cultural, civic, and community groups, or by minority groups, is being · excluded in the nation's major' cities and metropolitan areas by the economics of cable system construction and financing.