Economic considerations color every aspect of international dealings, and nations are just like individuals in that the lender sets the terms of its dealings with the borrower.
Conclusion (that is why)
A nation that owes money to another nation cannot be a world leader.
Evidence
Nations are like individuals: the lender sets the terms of its dealings with the borrower.
Evaluate
The evidence tells us that borrower nations .
The conclusion is trying to claim that borrower nations, "can't be world leaders".
It seems like this is setting us up for a Missing Link answer that takes us from what we know about borrower nations to what is being claimed in the conclusion about borrower nations.
Goal
Let's look for something like, .