User blog comment:- Darkchylde/Acnologia's Element?/@comment-173.87.12.242-20141211055642/@comment-4829046-20141214083636

Well, he did destroy a whole human country.

And you are heading into deep, deep, deep what-ifs there. I applaud you for that, but let's leave it at that. If it goes that way, then Mashima better give a REALLY good reason or at least follow the suggestions me or Nick have given. And considering how many predictions of the series have been correct, I doubt you will be too surprised when the actual reveal comes ;)

And if he was trying to protect humanity, then Future Rogue wouldn't have come to the past.

Like we have been saying again and again, what you suggest applies to his 'past self' not his 'present self'. But you can argue that his 'future self' is different from his 'present self' but that is unlikely given the events on Tenrou and also events of the latest chapters.