It's how they are trained.
"Never underestimate the value of staff planning".
Marines when planning consider all options of their enemy and how to close of any potential exits.
Yes they use predictive and gaming software to help but it is more the way they build a Marine officer and how they train them to think. The screening process for OCS / OCC incorporates this. That is why TBS is recognized as the world's finest school of Leadership.
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