The development of new technologies also increased their role in the security and defense sector. One of these technologies are also social networks. The significance of social networks is increasing in all areas of modern life, with political and national security are no exception. Although social networks are relatively new tool, the soft power in the form of influencing the opinions, perceptions and values of target audiences has long been a tool of states, which can be seen in the importance attributed to the discourse and education in totalitarian regimes or the meaning of propaganda in the Cold War. Since flexibility is one of the features of a successful shaping of public opinion, it is not surprising that new technologies, including social networks, are being used for this purpose. These are especially useful for various forms of psychological and information activity, where, unlike previous communication tools,allow more decentralized and uncontrolled dissemination of information. Perceptions play big role in shaping and the course of social life, where they determines the relation to an individual question, policy, state or group and by creating perceptions we can indirectly influence the defence and security policy, since the formation of discourse is a key element of securitization.