>>513001716 (OP)
USD needs to be backed by more than small arms. Try carrier groups, multiple years worth of artillery shell production per major war waged, intelligence, logistics and maintained hardware, and personnel with wherewithal to do so.
Good luck convincing everyone to use USD's if the money you pay for all that shit to keep the empire, continues to lose value, it's a self reinforcing system, but also a self destructing system.
USD tautology.