Except a nation with no debt and a negative trade balance has negative wealth.

You can't sneak negative trade balance into an argument about public debt.

A nation with no debt has the ability to take on more debt than if it already has debt.

" Zero national debt " means zero dollars left in circulation after taxation.

You can have debt for circulation while maintaining a net surplus in all accounts. For example Norway has a per capita debt of $42k USD while maintaining a surplus of $295k USD per capita.

It's similar to how a company like Apple holds debt of $108 B USD while maintaining a $162 B USD surplus.