From the story:
The exercise simulates a patrol taking on an enemy position without the use of indirect fire due to risk of causing civilian casualties. This in turn forces the Marines to rely on accurate small arms fire, said 1st Lt. Mark A. Greenlief, the executive officer for Bravo Company, 1/6. The purpose of the training exercise is to further develop the Marines’ ability to quickly acquire enemy targets and engage them, while minimizing the risk to civilians.
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