He could easily overwhelm any wizarding army/faction by raising an army of magically enabled Muggles, once he can access the technology. Since there are only tens of thousands of magical people in Britain, just converting 500 muggles to wizards would make Harry the dominant force in the magical world.
That's an interesting move, though it leaves out the organizational challenge and the amount of time needed for training.
And it seems unlikely that such a force could be kept secret from the wizarding world....
ETA: There is now a third thread, so send new comments there.
Since the first thread has exceeded 500 comments, it seems time for a new one, with Eliezer's just-posted Chapter 33 & 34 to kick things off.
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