A very long time ago, when the human race had not yet taken over the earth, every human had to struggle for his own survival. Those that were too weak were forced to starve to death, or were eaten by saber tooth tigers. Then, as human society "advanced," people invented the artificial concept of morals, which dictated, among other things, that the strong should protect the weak. As time went by, humans also created cities, which separated them from the forces of nature that they had come to fear, as well as governments, laws, police, etc, all of which served the ultimate purpose of maintaining an artificial order within the human race, so that humans, by and large, would no longer have to fear death by anything other than disease or old age, whether they are strong or weak (thus, it is easy to understand why deaths by any means other than disease or old age are labelled as "unnatural deaths"). The end result is that the human race has become a species of animal like no other: it lives within an unprecedented level of separation from nature (and even often believes that it can conquer nature); it sees the strong and weak individuals of its species as equals, and even sees the lives of its individuals as "sacred" (a concept that arises from the human concept of religion, something else that separates this species from others); and it has created and continues to maintain a set of regulations on itself so that it will always be separated from nature and continue to treat its strong and weak as equals, until the species is finally killed off in the eternal war of natural selection, becoming just another extinct species that once existed in the history of planet Earth.
The moral of the story? There isn't one - morals are an artificial concept, remember?
a long time ago people wanted to know who was the fastest Native American so they had a race. all the Native Americans were fast but some were slower. noone won noone lost. they all tied because when they were young they were taught never to leave each other bahind.