Quick question. What would your initial reaction be to hearing/seeing a real live E.T? Maybe mentally and technologically more advanced than our species?
To be honest... My initial reaction would be sheer fear. I would think first to protect myself and my family. Even if the E.T was not acting hostile, because how do I know what if any morals guide it.
Most humans act instinctively to danger, its hardcoded in our genes.
Can humans as a species, that has total dominion over earth and no predator to speak of - Accept the existance of another species as intelligent, advanced as their own??
IMO instinct would drive humans to war with any species we couldn't control or destroy.
Just look at what we do to ourselves/eachother everyday... hmm?