ALTHOUGH GUNS AND EXPLOSIVES FORM THE BACKBONE OF MOST TERRORIST ARSENALS, THE TERRORISTS' CAPACITY FOR DESTRUCTION HAS INCREASED DRAMATICALLY AS A RESULT OF THE INTERNATIONAL ARMS RACE, AND THE TECHNOLOGICAL DEVELOPMENTS OF THE MAJOR POWERS. AS A RESULT, MODERN WEAPONS AVAILABLE TO TERRORISTS ARE MORE POWERFUL, MORE ACCURATE, AND LESS COMPLEX THAN WEAPONS OF EARLIER TIMES. MODERN TECHNOLOGY GIVES INDIVIDUAL TERRORISTS THE CAPACITY TO KILL LARGE NUMBERS OF PEOPLE, OFTEN WITH LITTLE PERSONAL RISK. MODERN WEAPONS SUCH AS PORTABLE ANTI-AIRCRAFT MISSILES HAVE BEEN OBTAINED BY TERRORISTS THROUGH PURCHASE FROM ARMS TRAFFICKERS, OR THROUGH THEFT FROM MILITARY ARSENALS. IN CONTRAST TO GUERILLA ORGANIZATIONS, TERRORIST GROUPS ARE HIGHLY SELECTIVE IN THEIR WEAPONS CHOICE, AND GENERALLY PREFER THE LIGHTEST, SMALLEST, MOST RAPID-FIRING AND ACCURATE ARMS AVAILABLE. WITH SUCH DEVICES, THE TERRORISTS MAY OBTAIN DISPROPORTIONATELY LARGE EFFECTS FROM THE EMPLOYMENT OF MINIMAL RESOURCES. WHILE SOVIET ARMS ARE PROVIDED TO TERRORISTS AS A PART OF MOSCOW'S SUPPORT OF VARIOUS REVOLUTIONARY MOVEMENTS, AMERICAN WEAPONS ARE OBTAINED BY TERRORISTS THROUGH MORE CIRCUITOUS ROUTES, SUCH AS THE SALE BY THE VIETNAMESE OF WEAPONS CAPTURED IN THE ASIAN WARS. BETWEEN 1971 AND 1974, ALMOST 7,000 U.S. ARMY WEAPONS WERE STOLEN FROM MILITARY ARSENALS; MANY OF THESE WEAPONS WERE SENT TO THE IRISH TERRORISTS. ALTHOUGH THE STANDARD 9 MILLIMETER SUBMACHINE GUN REMAINS A PREFERRED WEAPON OF TERRORISTS, THE DEVELOPMENT OF MORE DEVASTATING FIREARMS, AND OF PLASTIC GUNS WHICH ARE NOT DETACTABLE BY AIRPORT METAL DETECTORS INCREASE THE POTENTIAL EFFECTIVENESS OF TERRORIST ATTACKS. POWERFUL WEAPONS MAY ALSO BE CONSTRUCTED FROM COMMON MATERIALS SUCH AS AMMONIUM NITRATE FERTILZER. GOVERNMENTS MUST MAINTAIN CONSTANT VIGILANCE SO AS TO PREVENT CATASTROPHIC TERRORIST ACTIVITIES. FOOTNOTES ARE PROVIDED. (TWK)