If the 'point of a gun' element was the major determinant in how much currencies are worth, Zimbabwe, which had and has a military sufficient to kill its own citizens, would never have had hyperinflation.
Hint: I was talking about imperialism, not "buy stuff with the national money, citizen!"
And if being a global superpower is the key to running an economy based on fiat money, how did it get that big in the first place?