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Alert state

Military forces on forms of threat

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Source updated June 10, 2026

An alert state, alert level, or state of alert is an indication of the state of readiness of a country's the armed forces for military action to respond to military attack, terrorism, or natural disasters. The phrase frequently used is "on high alert". Examples of scales indicating alert state are the DEFCON levels of the US military, South Korea's "Jindogae" system, and the UK Threat Levels. High alert states are synonymous with "red alert".

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This article is adapted from the Wikipedia article “Alert state”, written by its contributors and licensed under CC BY-SA 4.0. Fathomly has changed the layout, removed citation markers, navigation and maintenance notices, and adjusted punctuation. This adapted version is shared under the same license. For references, see the original article.

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Combat readiness

Combat readiness is a condition of the armed forces and their constituent units and formations, warships, aircraft, weapon systems or other military technology and equipment to perform during combat military operations, or functions consistent with the purpose for which they are organized or designed, or the managing of resources and personnel training in preparation for combat. Different armed forces maintain different levels of readiness for the troops to engage in combat, varying from minutes to months; economic considerations are a major factor in explaining the variation.

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