I have a theory about the secret behind One Piece story.
It may sound strange, and I don't know if it was given before.
Here it comes…
The One Piece story is going on at a time more than 800 years ahead of today.
For accomplishing the dream of New World Order, USA and Israel desperately nuked the entire world to conquer it. They accomplished it, but the outcomes of this event destroyed all the technology on earth. And because of the high radiation, new species (ogres, weird animals, devil fruits, etc) started to appear.
The ancient weapons in the story are probably atom bomb and hydrogen bomb. Or other mass destruction weapons like them, like biological weapons or HAARP.
The new "World Government" prohibited research about the ancient past, because they don't want the people to learn the massacre their ancestors did.
After this war, they gathered all the remaining science books and documents, and kept them for themselves. This explains all the high tech science stuff appearing, like cyborgs and Vegapunk being 500 years ahead of worlds knowledge.
And the pirates are the heroes who are trying to reveal this dark history.
And One Piece is the "truth" behind the World Government. Gold Roger, by a little lying, made people go behind this truth. When someone finds out this "treasure" the World Government will be in real trouble.
So, what do you think about this conspiracy theory?