A United States marine is rightly seen as being a tough guy that is willing to push themselves to the absolute limit of what is humanly possible. They are also able to withstand a lot of pain, but it is perhaps fair to say that they do require a certain degree of luck on their side as well.
Take the story of Jack Lucas as a prime example of how some marines are indeed extremely lucky. Young Jack was desperate to enlist that he lied about his date of birth, so he actually joined when he was only 13 years old, as this was during the time of World War II.
Upon joining, he quickly saw action and somehow managed to survive being blown up after he dove on two grenades in an attempt to save the rest of his team. If that was not enough, he then recovered from that blast and had another miraculous escape when he jumped out of a plane and both of his parachutes failed to open. Somehow he survived the fall, which really does show how you need to be extremely lucky at times in order to survive whatever is thrown at you.