For the half century of its existence as an independent yet besieged state, Israel has had a coherent and generally effective national-security doctrine, predicated upon the existence of a mass, reserve-based army, and an offensive operational style. Despite a well-deserved reputation for innovativeness in the tools and techniques of war, the Israeli defence establishment has generally been conservative in its outlook, preferring aggressive incremental change to wholesale reform or transformation. Today, however, new geopolitical conditions, a changing technological environment, evolving threats and, perhaps most important of all, profound changes in Israel's society and economy, have come together to force just such dramatic change. [ABSTRACT FROM AUTHOR]