ALTHOUGH THE PRACTICE OF INTERNATIONAL TERRORISM HAS BECOME ALL TOO FAMILIAR, ACTS AGAINST MARITIME OBJECTS ARE RELATIVELY RARE AND USUALLY NOT WELL PUBLICIZED. HOWEVER, THERE HAVE BEEN SEVERAL ATTACKS ON MARITIME TARGETS, INCLUDING THE 1971 ROCKET ATTACK ON A TANKER UNDER ISRAELI CHARTER, THE 1973 SINKING OF A TOUR SHIP BY THE BLACK SEPTEMBER ORGANIZATION, AND THE 1974 HIJACKING OF A FREIGHTER BY THE MOSLEM INTERNATIONAL GUERRILLAS. THE OCEANS CONTAIN MANY SUCH ECONOMIC ASSETS THAT COULD BE THREATENED BY TERRORISTS; E.G., OFFSHORE OIL PLATFORMS AND MINING RIGS. INTERNATIONAL LAW ASSIGNS PRIMARY JURISDICTION FOR AN INCIDENT TO SOME NATION (FLAG STATE FOR VESSELS UNDER MOST CIRCUMSTANCES; LITTORAL STATE FOR EXISTING CONTINENTAL SHELF STRUCTURES OR STRUCTURES WITHIN THE TERRITORIAL SEA). AT PRESENT (1978), THE JURISDICTIONAL FRAMEWORK IS AN INADEQUATE BASIS FOR ALLOWING A STATE TO PROTECT ITS ASSETS AGAINST TERRORISM BEYOND ITS TERRITORIAL SEA. RESOLUTION OF THIS PROBLEM THROUGH ESTABLISHED INTERNATIONAL LEGAL FORUMS, ESPECIALLY THOSE DEALING WITH LAW-OF-THE-SEA (LOS) MATTERS, WILL BECOME ENTANGLED IN BROADER POLITICAL ISSUES. HOWEVER, IF AN LOS TREATY EMERGES THAT IS ACCEPTABLE TO THE U.S., IT IS LIKELY TO PROVIDE AN IMPROVED BASIS FOR NATIONAL ACTION. IN THE CASE OF VESSELS, AN AMPLE U.S. LEGISLATIVE MANDATE EXISTS FOR PREVENTIVE AND ENFORCEMENT ACTIVITY BY U.S. ENFORCEMENT AGENCIES. IN THE CASE OF STRUCTURES, ADDITIONAL CLARIFYING AMENDMENTS WOULD BE USEFUL. GENERALLY, PREVENTIVE PLANNING TO DATE IS INADEQUATE. RECOMMENDATIONS ARE PROVIDED REGARDING SPECIFIC LEGISLATIVE AMENDMENTS, U.S. AGENCIES' RESPONSIBILITIES AND PLANNING, CONTINGENCY PLANNING BY INDUSTRY, PROJECTING U.S. POLICY, AND DESIGN IMPROVEMENT FOR OCEAN VESSELS AND STRUCTURES. REFERENCE NOTES ARE INCLUDED. (KBL)