First of all, Covenant, you should be more careful in your choice of hunting partners. I am referring to the people who are the subject of this discussion, the pilots. What slob hunters do is no concern of this thread. The pilots I hunt with are honourable, responsible and skilled and, indeed, they look with disgust on the type of hunters you describe.
I would argue, since you raise the point, that some americans are more culturally equipped to use a firearm than some other national groups (not all, take the tribal Afghanis as an example). The reason is that the effective use of a firearm requires ABILITY and RESOLVE. Since more american members of our subject pilot group have received official training in firearm use, have experience in hunting, have family exposure to firearms, take part in shooting sports and have no official prohibition on the use of firearms it is inevitable that they will have greater ABILITY in the use of firearms than other less practiced groups. Sorry, but as a practical matter there it is. In addition, since these same people have often been trained in the use of firearms to resolve confrontations and since the US culture in general accepts firearm use in self defence there is a greater RESOLVE to use a firearm in this group than in other groups (individual moral choice honoured, respected and accepted) . Therefore, I think we can say that US pilots are culturally better equipped to use firearms than some other national groups. No GENETIC difference here, just the national or cultural matter of practice and exposure which encourage skill in use and determination to use.
Never had the need to shoot anybody myself, at least not with a handgun when I could see their face. I can tell you, in my case, that in hunting you quickly get over the "overexcitement" of your first shot at game. After recovering from that first twitching session it did not recur regardless of what the target has been. Never know, of course, but I suspect that in an emergency and not having time to reflect on the morality of the situation I would probably treat a terrorist just like a funny shaped Kangaroo. After effects may not be pleasant but better than the eternal alternative.
Tallyho, judy, splash