I don't think that killing non-human animals is necessarily wrong, but I don't think that killing humans is necessarily wrong, either.
For me, ability to defend oneself has nothing to do with the rights you deserve. The most important point is sentience and ability to feel pain. Hunting for food is more ethical than the commercial meat industry, since the animals that are victims of hunters live relatively good lives and, as long as the hunter is a good shot, die a quick & painless death. Even if the hunter isn't a good shot, their suffering will be insignificant in comparison to the suffering of most animals that we eat.
I don't think that hunting for sport is ethically justified, but, like hunting for food, it's still more justified than the methods of the commercial meat industry. Most of us don't need to eat animals to survive or remain healthy - we do so because they taste nice. Just as we receive minor pleasure from the taste of certain animals, hunters receive minor pleasure from hunting, and I find it quite hypocritical when people who accept the extreme amount of suffering that we inflict on animals so we can enjoy their taste start to criticize the lesser amount of suffering that hunters inflict on their prey so that they can enjoy the activity of hunting. That said, I welcome any opposition to hunting for sport that involves causing a lot of distress to the animal, whether that opposition is hypocritical or not.
To clarify my position: I don't believe that it is wrong to kill most animals for food, as long as they are treated well during the time they are alive, and are killed using quick, painless methods. However, if we're going to allow that, we would also have to allow killing infant babies for food (as long as the family consents). The same applies to medical experimentation. It's not necessarily wrong to use animals for medical experimentation, but if we do that, we have to accept that infant babies are also allowed to be experimented on (again, with the consent of the family). In fact, in this case, it would probably be more ethical to use the babies: since they are human, they would probably provide more accurate results.
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"There is no idea, however ancient and absurd, that is not capable of improving our knowledge."