This group consists of people who live in tornado, hurricane, flood, wildfire, earthquake or heavy snowfall-prone areas and want to be prepared for possible emergencies. They invest in material for fortifying structures and tools for rebuilding and constructing temporary shelters. While assuming the long-term continuity of society, some may have invested in a custom-built shelter, food, water, medicine, and enough supplies to get by until contact with the rest of the world resumes following a natural emergency.
The U.S. Department of Homeland Security (DHS) in their "If You See Something, Say Something" campaign says that "the public should report only suspicious behavior and situations...rather than beliefs, thoughts, ideas, expressions, associations, or speech...". However, it is alleged that a DHS list of the characteristics of potential domestic terrorists used in law enforcement training includes "Survivalist literature (fictional books such as Patriots and One Second After are mentioned by name)", "Self-sufficiency (stockpiling food, ammo, hand tools, medical supplies)", and "Fear of economic collapse (buying gold and barter items)".
The increased inflation rate in the 1960s, the US monetary devaluation, the continued concern over a possible nuclear exchange between the US and the Soviet Union, and perceived increasing vulnerability of urban centers to supply shortages and other systems failures caused a number of primarily conservative and libertarian thinkers to promote individual preparations. Harry Browne began offering seminars on how to survive a monetary collapse in 1967, with Don Stephens (an architect) providing input on how to build and equip a remote survival retreat. He gave a copy of his original Retreater's Bibliography to each seminar participant.
Despite a lull following the end of the Cold War, survivalism has gained greater attention in recent years, resulting in increased popularity of the survivalist lifestyle, as well as increased scrutiny. A National Geographic show interviewing survivalists, Doomsday Preppers, was a "ratings bonanza" and "the network's most-watched series", yet Neil Genzlinger in The New York Times declared it an "absurd excess on display and at what an easy target the prepper worldview is for ridicule," noting, "how offensively anti-life these shows are, full of contempt for humankind."
To me, the best option is to store emergency food. How much? If you have none, store enough for a few days. If you have enough for a few days, get enough for a week. How much you store depends on what time frame you think you're at risk for having to be completely independent. The early settlers of the southwest liked to store enough food for a whole year and still do to this day!