The prospect of world war has almost vanished with the end of the Cold War. Apart from the regional hostilities which are with us still, there is a different threat to world peace in the shape of terrorist groups in widely separated places attempting to deliver political and religious messages in highly dramatic terms. In their single-mindedness and despair they may be tempted to use methods which lead to injury and destruction on a cataclysmic scale. This is a different scenario from past types of terrorism when specific objectives were thought about, targets were identified and marked down, operations were planned and executed and, generally, deaths and injuries were not of massive proportions.