The U.S. made machine guns.
Need I say more?
That doesn't mean absolutly nothing. I didn´t asked who invented what, I asked who have the better army in your opinion.
For example,(and we cant be sure of nothing)Russia have the best Nuclear Bomb ( the TZAR bomb) but USA have more 3 aircraft carriers than russia. Russia have more tanks, and a better trained soliders. In other hand, USA have more allies.
I dont care about who invented what....