National security is an important concept which has often been mistakenly used to refer to protection against external threats. With people gaining better knowledge of the term security, national security has become a complex term that involves human as well as environmental security. For a nation to feel completely secure, it should not only be protected against external threats and aggression but also against internal problems that might make its citizens feel less safe. National security also includes local or internal security which is often defined separately as if it was not a part of the broader term. We must understand that if a person feel threatened in his own country due to any reason such as racism, religious persecution or environmental problems, then he cannot consider his country secure for himself. .

             Local insecurity leads to national disturbance which might make a country and its people feel vulnerable. For many people, national security refers to "the capacity of a nation to protect itself from external invasions and internal coups. National safety often means different things to developed and developing countries. Since developed countries possess a tremendous amount of resources, they are able to invest in military technologies that are intended to guard their nations' shores and other territories. Developed nations (and some developing nations) often use their own advanced missile systems, central intelligence, and other military human power-capabilities, to protect themselves from external invasions and internal coups. For example, to the United States government, national safety means fortifying its nation with the strongest and smartest weaponry and soldiers in the world." (Peter) But this is an incomplete definition of national security because it doesn"t take into account environmental security and internal threats. A more comprehensive and relevant definition would thus be the one given by historian Howard Zinn who stated: "I define national security as making sure every American has health care, employment, decent housing, a clean environment.