The outline of human history over the last two thousand years is framed by armed conflict. Many would like to overlook this simple historical reality, and the perilous consequences of ignoring military affairs. The advantage the West now enjoys is the product of several developments in political and social domains culminating in what can be called a Military Revolution. The creation of powerful states as the overarching social organization is an example of one such revolution, which supported a series of smaller innovations and changes in the way the West fought its wars. These smaller changes are “revolutions in military affairs.” These revolutions do not have to be tied to technology. Britain generated an advantage over France by creating a financial system which substantially altered its ability to sustain the conduct of war in the eighteenth century. History reveals the degree of political, social, economic and technological adaptation needed to maximize security and minimize the consequences of failure. The study of history is necessary to insure that we do not have to fight wars more often, or at far higher cost in human terms.