BTW – my father was a marksman in the US Army. He learned it during his 2 year tour of duty. He was drafted in 1952, not during any wartime. He was not in Yeshiva anyway – even back then they only accepted the best students.
He never did anything with it after he came back home. He didn’t carry a gun or shoot any terrorists. But he still had the skills many years later. He taught me to shoot and was still a crack shot, even with aging eyesight and shaky hands.
But we always considered it just a game or hobby. We never considered that there might be a question of bringing guns to shul.