Those were extremely problematic memories, I'm sure, for a great many people who served on the Bunker Hill. There are a lot of instances like that. It's not clear why one individual develops PTSD and another does not, nor is it completely clear exactly how many military members have PTSD. The manifestations can come quickly after a particular incident or not manifest for decades. I don't think there is a significant difference in the military experience, except that probably the likelihood of being helped or having support, or the sense that the mission was worth it, plays a role.
I spoke at some length with a Canadian Army officer who had been in Rwanda some years ago. He had very explicit PTSD. It was extraordinarily difficult for him, but buddies of his who were in the same unit, in exactly the same settings, had no such problem. I think that if we could identify what it is that makes one service member more resilient compared to another, we'd be well served.
However, I do think that pre-treatment with cannabinoids.... There is some evidence that this may be beneficial. Pre-treatment with cannabidiol or possibly some combination of CBD and THC may be beneficial in preventing the neurological sequence of events that results in PTSD. We don't really know yet.