I think perhaps the Rangers ought to adopt local practices: declare the blood feud against the back shooter’s clan and wipe them out completely. That would probably bring a quick halt to these kind of shenanigans. Afghans have some significant anger management problems, as well as a predilection toward banditry as a career choice; however, what keeps most of them honest is the prospect that if they murder another Afghan they will have his whole clan after them, AND their family members, for bloody revenge. With infidel foreigners you don’t face this issue at all.

Three Army Rangers Killed in Afghanistan in "Insider Attack"

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