History of the national security concept development in the political science of the 20th century
Importance Nowadays most theoretical approaches to studying the national security fail to provide certainty and properly evaluate some methodological aspects of respective strategies and their formation. This requires to theoretically revise the category by analyzing the existing scientific legacy.  Objectives The research delves into the evolution of the national security in the political science of the 20th century and identifies distinctions in integrating and implementing the devised approaches into practices of various countries.  Methods I apply methods of historic-comparative and problem-chronological analysis.  Results Studying the phenomenon of national security comprehensively, it is necessary to consider various contradictory viewpoints and approaches in this area, which complement each other. As the analysis of the national security history in the political science of the 20th century shows, there is a variety of viewpoints. Hands-on aspects of political science findings are illustrated through various countries, thus proving that the USA was the leader in terms of completeness and efficiency of doctrine instruments on the national security from economic perspectives.  Conclusions and Relevance In the 20th century, States evolved in terms of their attitude to their own security moving from the unipolar to multipolar world as the world order system unfolded, and from primitive technologies to nanotechnologies as waves of innovations advanced. As a result, national security models morphed from cameralism to institutionalism, seeing the rise of new teachings on national economic security.