Animal Rights
Based on the DNA similarities of humans and animals, animals have just as much right to life as we do. For the price of a couple of our B-2 bombers, we could develop a plant-based diet with supplements. This would have the added benefit of eliminating animal fats from our diet and add to our life-span.
Was it wrong for our ancestors to kill and eat animals? No. It was survival of the fittest and that was all they knew. But, it is now wrong to herd and kill animals.
If we eliminate the idea that it is okay to kill to survive, it might start translating to show that killing humans is also wrong.