How does the uneven distribution of resources encourage specialization?

Lets say that we ( USA ) have an Unequal distribution of resources with Canada , this means that one of us will have the upper hand , saying that we or Canada will have a better stock of food, medicine , and weapons.

In that case whoever has the underhand will have to borrow from the other one , and than eventually we will have an even trade again.

I really hope that this helps a lot.

  

The answer would be giving evaluation .