Humans are as much a part of nature as tree frogs or algae. If humans are doing it, it is natural.
Cool. So if Al Qaeda or ISIS murder and maim innocent men, women and children, its all natural, because humans (such as they) are a part of nature, as much as tree frogs or algae are. After all, they're doing it, so it must be a part of nature, right? Okay, what am I missing here, given your exact (and only) words above? I'm asking politely (this go-around).