pull down to refresh
the nat resources -- the most persuasive of which in the IR is coal -- is definitely a regularly invoked candidate... but it's not from the empires (it's home-grown), and many other civilizations (e.g., Yangtzee delta in China) had remarkably refined energy processes for coal. Still, no dice.
reply
I might argue that it was the unparalleled access to natural resources: the european colonial empires are rising and have access to whole continents-worth of resources and the ability to move the resources around.
Or do you suggest that it was common law? Blackstone publishes his big ol' compendium of common law in the middle of the 1700s.