Please walk through the steps and prove that.
How about making it easy, and presume nobody in the US buys anything German at all. (Tourism, etc. counts.) Now why they would choose to do so is another matter and I’m not saying they ought to. But it’s an oversimplified presumption to your oversimplified mind.
Then it would be impossible for the US as a whole to be spending anything in Germany.
Then whatever bonds the US must issue to make up for its net loss of cash, will not be due to having spent any cash in Germany.
Expand that to trade with the rest of the world.
What’s difficult to see?
Of course you’re going to be spritzenpoppen that this is impossible or at least highly undesirable.