A while ago I did a bit of a dive into this conflict. It is very interesting, however this is not new to this conflict, but been going on for a long time. The US did it in vietnam indigenous troops in the "scout" operations. In a thing like that you only need a second to swing things your way. Everything from eating specific foods so you sweat smells a specific way, BTW the North Koreans gave this a go for a long time, but after the issues in NK the stature of the humans have changed so much over their South Korean neighbors they are quiet easy to spot now. Plus they had this issue of jumping ship no matter how many of their loved ones Kim held.
Anyhoo, I think this is a bit different, this is a "long term" plant, someone that does need to pass as the people in the group they are in. Their issue is for a large part the group they are looking for just is not there in the numbers they want you to believe. Sure there are nutz but that is a "fringe" there are always "fringe elements".
Really just an excuse to talk about Rhodesia, as I am just interested in the subject.
Try the following books. One goes into the....issues...I guess I will say between the SAS and the Selous Scouts, with a sprinkle of the RLI in there for good measure. I can't find the title in my history, but there is a good one on the RLI as well and getting into that outfit was not a walk in the park. And contrary to what many think, all of these have members of different races, including Asian IIRC. It was not a "white" thing. It was a country thing.
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