Homeland security

Homeland security is an American national security term for "the national effort to ensure a homeland that is safe, secure, and resilient against terrorism and other hazards where American interests, aspirations, and ways of life can thrive" to the "national effort to prevent terrorist attacks within the United States, reduce the vulnerability of the U.S. to terrorism, and minimize the damage from attacks that do occur." According to an official work published by the Congressional Research Service in 2013, the "Homeland security" term's definition has varied over time.
"Despite the [published] definition, mission statement, and vision [all of which have changed since 9/11], there is no consensus among practitioners and the public as to what the term Homeland Security actually means. Different groups view it differently [fn omitted]. The extremes of opinion are represented, for the narrow view, by those who feel homeland security is only about terrorism. They believe focusing on anything additional dilutes, distracts, and weakens the homeland security mission. 
Others say its focus is terrorism and natural disasters. Still others claim homeland security is about ‘all hazards’ (terrorism, man-made disasters, and natural disasters). To some, homeland security is focused on ‘jurisdictional hazards’ (i.e. homeland security means different things to different jurisdictions depending upon that jurisdiction’s particular hazards, risks, and level of preparedness). Examples of some of the jurisdictional hazards include hurricanes, tornados, flooding, and earthquakes. At the other extreme, the broad view of homeland security advocates that homeland security is about everything – that it implicates almost every sector "
Homeland security is not constrained to terrorist incidents. Terrorism are violent, criminal acts committed by individuals and/or groups to further ideological goals stemming from influences, such as those of a political, religious, social, racial, or environmental nature. Within the U.S., an all-hazards approach exists regarding homeland security endeavors. In this sense, homeland security encompasses both natural disasters and man-made events. Thus, the domain of homeland security must accommodate a plethora of situations and scenarios, ranging from natural disasters (e.g., Hurricane Katrina, Irma) to acts of terrorism (e.g., Boston Marathon bombing, September 11 attacks).
The term came about following enactment of the Homeland Security Act of 2002 and reorganization of many U.S. government civil agencies effective March 1, 2003, to form the United States Department of Homeland Security after the September 11 attacks, and may refer to the actions of that department, the United States Senate Committee on Homeland Security and Governmental Affairs, or the United States House of Representatives Committee on Homeland Security.
The term, "Homeland Security" is not to be confused with the U.S. Department of Homeland Security (DHS). In its February 15, 2001, Report, the U.S. Commission on National Security/21st Century, said the United States must change how it operates in the area of homeland security. The report recommended the creation of what was ultimately called the Department of Homeland Security. "<ref name=The Phase III Report of the U.S. Commission on National Security/21st Century, February 15, 2001 (p. viii)</ref> 
DHS was formed by the Homeland security Act of 2002. The term, homeland security, is not the same as the Department of Homeland Security (DHS). DHS is an executive branch agency. "
See also.
U.S. specific: