The book analyse the explanatory power of offence-defence theory. This theory seeks to explain war and peace in international relations. It will proceed by examining the role of technology in offence-defence balance in three phases. The first phase deals with conventional warfare which mainly signifies the pre -nuclear age. The second phase denotes the period after the end of the Second World War which is interpreted as the nuclear era. The third phase will examine the period of information warfare by elaborating on the relevance of offence- defence balance theory.