National defense science and technology and military affairs are two closely related fields. The relationship between them can be summarized as follows: military needs have contributed to the formation and development of the field of national defense science and technology; The development of national defense science and technology provides the army with the necessary material and technical means, and at the same time, it will promote the continuous reform in the military field and even trigger a military revolution; Military reform and war have put forward new demands and will provide new impetus for the development of national defense science and technology. This mechanism or logic of the relationship between national defense science and technology and military affairs is an objective law. In recent years, the issue of the new military revolution has become a hot topic of concern. In fact, the new military revolution is the reflection of the above objective laws under the specific conditions of the rapid development of military high technology. Of course, the relationship between national defense science and technology and military affairs will also be influenced by political and economic factors. 1. Military demand is a powerful driving force for the development of national defense science and technology, and social demand is the driving force for the development of science and technology. Engels once pointed out: "Once there is a technological need in society, this need will promote science to more than ten universities" (The Complete Works of Marx and Engels, Volume IV, People's Publishing House, 1972, p. 505). Similarly, as an important part of the whole science and technology, national defense science and technology is the product of social special demand-military demand, which can promote the development of national defense science and technology more than any other force. Since the emergence of the country, in order to safeguard the territorial sovereignty of the country and safeguard and obtain the fundamental strategic interests of the country, national defense and war between countries have emerged. In order to consolidate national defense or win the war, all countries try to master more advanced military technical means, so they organize special forces to develop weapons and equipment, and national defense science and technology came into being. Because the invention and use of new weapons can create huge military advantages, the "most naive public theorist" is more and more aware of the important influence of national defense technology on military affairs and wars from the fact that "the pistol beats the iron of the sword", so national defense technology is paid more and more attention by governments all over the world. As Ding Bernard, the founder of science of science, said: "Since ancient times, improving war technology always needs science more than improving peaceful life. This is not because scientists are bellicose, but because the need of war is more urgent than other needs. Monarchs and governments of various countries are not so willing to provide subsidies for other research work, but are willing to provide funds for military research work, because the scientific community can develop new equipment, which is extremely important in the military because of its novelty. " Seeking truth from facts, it is pointed out that the development of weapons and equipment to meet military needs is the driving force, main task and purpose of the development of national defense science and technology. After the end of World War II, from 1950s to the end of 1980s, during the 40-year-long Cold War, the United States and the Soviet Union had a fierce arms race. Both countries implement the strategy of giving priority to the development of national defense science and technology, requiring the national defense science and technology department to develop a batch of advanced weapons and equipment for the army, and surpass each other in tactical and technical performance from generation to generation. Under the strong stimulation of military demand, the development of national defense science and technology of the two countries has gained a strong impetus and reached extreme prosperity. Many other countries are forced to take corresponding countermeasures to accelerate the development of national defense science and technology in this state of war. According to statistics, by the mid-1980s, the total annual defense research expenditure of countries around the world was as high as $80-654.38+00 billion. In this way, driven by the military demand of the Cold War, the development of national defense science and technology has entered the era of military high technology. After the end of the cold war, major countries in the world have adjusted their military strategies and cut their military expenditures. The demand of the army has shifted from focusing on the quantity and quality of weapons and equipment to focusing on its high quality. Therefore, national defense science and technology has entered a new era of focusing on the development of high-tech weapons and equipment, that is, a new era of "whatever weapons are needed in any battle". Since the early 1990s, the U.S. Department of Defense, the Joint Chiefs of Staff of the U.S. Army and the three armed forces have studied and put forward the military requirements of the U.S. Army every year, and at the same time formulated and adjusted the development plan of national defense technology and weapons and equipment according to this demand. For example, in 1996, the US military determined the future new military requirements of 1 1. In order to meet these military needs, the basic research plan, the national defense science and technology field plan and the joint operation science and technology plan were formulated respectively. These plans clearly define the scientific and technological fields to be studied and developed and the performance requirements of weapons and equipment to be achieved. Russia, Japan and western European countries have taken similar measures. Because the future military demand is mainly the demand for information warfare capability, the development of national defense science and technology in relevant countries is closely focused on information warfare technology, C3I system, precision guided weapons and other military high technologies. To sum up, national defense technology is constantly developing under the impetus of military or national defense needs. The country can't be undefended for a day, and national defense can't be without technology for a day. Looking forward to the future, the national defense science and technology of all countries in the world will continue to develop under the constant promotion of military demand, and will move towards high technology with the high technology of military demand. Second, the influence of national defense science and technology development on weapons and equipment. Military demand drives the development of national defense science and technology. In order to meet the military needs, the development of national defense science and technology must constantly develop new weapons and equipment, which will inevitably have a major impact on weapons and equipment, that is, military technical means. Generally speaking, the influence of national defense science and technology directly engaged in the development of weapons and equipment on the development of weapons and equipment is comprehensive and decisive. This is mainly manifested in: the principle and types of weapons and equipment are constantly diversified, the structure is gradually complex, and the performance is improving day by day.