There probably is such a conspiracy theory, or many based on the same theme. Occam’s razor applies though - it’s far simpler to just assume that Putin is a self-aggrandizing dictator who dreams of conquest (what do you get for a girl who already has everything?). After all, if it looks like a selfish asshole, and it swims like a selfish asshole, and it quacks like a selfish asshole, then it probably is.

Of course, there are many groups within the military-industrial complex who are happy to take advantage of his behavior.