In the traditional "Maneuver Army" a "doctrinal task" for a maneuver unit is something that must be done, and it must be paired with a "doctrinal purpose" to be a complete mission statement.
"A Co will attack to destroy the enemy in Engagement Area Zulu"
"B Co will conduct an area defense to deny the enemy access to the fastest route to Objective Wrench"
"C Co will conduct a raid to disrupt enemy logistics in Sector 5"
In the Maneuver world, where we are moving men and equipment around the battlefield, the end state is defined with regards to enemy, friendly, civilian, and terrain. Such as:
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