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Theatre (warfare)

Military organization
Latvian platoon at Camp Lejune.jpg
Typical units Typical numbers Typical commander
fireteam 3–4 corporal
squad/
section
8–12 sergeant
platoon 15–30 lieutenant
company 80–150 captain/major
battalion/
cohort
300–800 lieutenant colonel
regiment/
brigade
2,000–4,000 colonel/
brigadier general
division/
legion
10,000–15,000 major general
corps 20,000–40,000 lieutenant general
field army 80,000+ general
army group 2+ field armies field marshal/
five-star general
region/
theater
4+ army groups Six-star rank/Head of state

In warfare, a theater or theatre (see spelling differences) is an area or place in which important military events occur or are progressing. A theater can include the entirety of the air space, land and sea area that is or that may potentially become involved in war operations.

In his book On War, Carl von Clausewitz defines the term as one that:

Denotes properly such a portion of the space over which war prevails as has its boundaries protected, and thus possesses a kind of independence. This protection may consist in fortresses, or important natural obstacles presented by the country, or even in its being separated by a considerable distance from the rest of the space embraced in the war. Such a portion is not a mere piece of the whole, but a small whole complete in itself; and consequently it is more or less in such a condition that changes which take place at other points in the seat of war have only an indirect and no direct influence upon it. To give an adequate idea of this, we may suppose that on this portion an advance is made, whilst in another quarter a retreat is taking place, or that upon the one an army is acting defensively, whilst an offensive is being carried on upon the other. Such a clearly defined idea as this is not capable of universal application; it is here used merely to indicate the line of distinction.

Theater of operations (TO) is a sub-area within a theater of war. The boundary of a TO is defined by the commander who is orchestrating or providing support for specific combat operations within the TO.

Theater of operations are divided into strategic directions or military regions depending whether it's a war or peace time. The United States Armed Forces split into Unified Combatant Commands (regions) that are assigned to a particular theater of military operations. Strategic direction is a group of armies also known as task (field) forces or battlegroups.

Also in the US Armed Forces the term of strategic is often associated with missile command (troops) dropping word missile out of use such as the United States Strategic Command. However it is an important strategic command that could be effectively deployed in any theater of military operations. A strategic command or direction in general essence would combine a number of tactical military formations or operational command. In modern military, a strategic command is better known as a combat command that may be a combination of army groups.


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Wikipedia

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