At the time of World War II, it was Vannevar Bush who first proposed the idea of linking science to war by developing new weapons. He demonstrated that technology was the key to win a war and hence on his proposal, formed a new organization was formed named National Defense Research Committee (NDRC), by the then President Roosevelt bringing together government, military, business, and scientific leaders to coordinate military research. This committee led research in developing new weapons where bush supervised the Manhattan project and developed the first atomic bomb and thus securing victory of the allies. Bush's work not only helped the Allies win the war, but it changed the way scientific research was done in the U.S.
Followed by Bush, here comes Nobert Wiener who coined the term cybernetics, a new science of control mechanisms in which the exchange of information would play a central role. He focused on the problem of destroying enemy airplanes. He designed the “antiaircraft (AA) predictor” which would characterize an enemy pilot’s zigzagging flight, anticipate his future position with the help of Radar, and launch an antiaircraft shell to destroy his plane. The model then emerged as new part of science, the science of control systems, CYBERNETICS.
During 1930, publishing of newspapers was banned. The three closely related sciences which engaged in calculating the enemy were: Operational research, game theory, and cybernetics. Weiner divided the enemies into two categories, and regarded them as devils. One was the "Manichean devil" "who is determined on victory and will use any trick of craftiness or dissimulation to obtain this victory." The other, the "Augustinian devil" was characterized by the "evil" of chance and disorder but could not change the rules unlike the “Manichean devil”.
In the First World War science had certainly played a huge part in chemical synthesis for explosives, poison gas, aeronautics and much more. In World War Two the scientific community was thoroughly mobilized to serve the state for military ends, and this led to the continuing close connection between science and the state in the following decades. As time passes with the advancement of technology new graduates were allocated to all the important areas of defense research. By twentieth century science has become the language of war. Mutual interest in winning the war, reinforced by financial support, permanently linked the military and science in a web of cross-fertilization that continues today.
1)Wikipedia technology used in defense system
2)Cybernetic warfare : Computers and cold warfare by C Warfare