CLAIMING A RIGHT TO THE USE OF MILITARY FORCE, ISRAELI COMMANDOS ATTACKED THE BEIRUT AIRPORT ON DECEMBER 28, 1968, 2 DAYS AFTER ARAB GUERRILLAS DAMAGED AN ISRAELI PLANE AND KILLED A PASSENGER IN ATHENS. AFTER HEARING LEBANON'S CHARGE THAT ISRAEL HAD COMMITED A 'WANTON AND PREMEDITATED ATTACK,' THE UNITED NATIONS SECURITY COUNCIL CENSURED ISRAEL AND DID NOT AGREE WITH THE ISRAELI COUNTERCHARGE THAT LEBANON HAD ASSISTED TERRORIST ORGANIZATIONS. ADDITIONALLY, SUCH MILITARY ACTION UNDERTAKEN BY REGULAR FORCES OF ANY GOVERNMENT AGAINST A FOREIGN STATE COULD CONSTITUTE A VIOLATION OF THE UNITED NATIONS CHARTER. THUS, IN THE ABSENCE OF IMPARTIAL FACTFINDING PROCEDURES, THE STATE THAT ACTS OVERTLY AND ON A LARGE SCALE IS MUCH MORE LIKELY TO BE REGARDED AS THE INITIATOR OF THE AGGRESSION. IN EFFECT, TRADITIONAL LEGAL CRITERIA CREATE AN ASYMMETRY IN FAVOR OF THE USE OF COVERT AND IRREGULAR FORMS OF VIOLENCE ACROSS INTERNATIONAL BOUNDARIES. ANALYSIS OF LEGAL PERSPECTIVES ON REPRISALS, CONSIDERED IN LIGHT OF THE BEIRUT AND ATHENS RAIDS, INDICATES THAT REPRISALS CAN BE JUSTIFIED ONLY IF THEY CHALLENGE THE PERPETRATOR OF A PREVIOUSLY COMMITTED ILLEGAL ACT, IF THE CLAIMANT STATE ATTEMPTS REDRESS FROM THE TARGET STATE BEFORE RETALIATING, AND IF THE DAMAGE INFLICTED IN THE REPRISAL IS ROUGHLY PROPORTIONAL TO THE DAMAGE INITIALLY INFLICTED. WITHOUT A MODERN LEGAL DOCTRINE TO DEAL WITH SITUATIONS OF PROLONGED QUASI-BELLIGERENCY, THE INQUIRY INTO THE JUSTIFICATION FOR AN INDIVIDUAL ACT OF REPRISAL IS NECESSARILY INCONCLUSIVE. THERE IS NO AGREED WAY TO FRAME THE BASIC ISSUE CONCERNING THE RELATIONSHIP BETWEEN THE 'LIBERATION' ACTIVITY OF THE PALESTINIAN GUERRILLAS AND THE LEBANESE TARGET OF THE REPRISAL. FOOTNOTES ARE PROVIDED. (TWK)