Variable: Defense (protection)

Protection from danger, attack, or injury is defined as a requirement by most social entities, from individual to nation. Collective responses to this need vary and are linked directly to other variables within the human ecosystem framework, including capital, materials and technology. Allocation and distribution of collective resources to defense can also result in the diminishment of other social institutions, such as education or health care.

Societies' ability and means of making war have changed over time, and can be measured in a variety of ways. These include economic cost or benefit (per capita expenditures of GNP on defense; direct defense-related profit to business and industry supplying goods and services), human cost or benefit (loss of life or changes in secondary school enrolment during wartime), social costs or benefits (changes in identity, e.g. Republican to Democrat or vice versa; norms; or traditional hierarchies of power and status).

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