America is billions of dollars in debt, and has never once made an attempt to actually pay its debts.
This is false, USA is always paying debt in full and on time, which is why it can continue to borrow cheap.
What you are probably thinking of, is that USA should stop taking on new debt. But since they don’t have to stop, why should they?
The huge difference between USA and a struggling economy like Pakistan, is that Pakistan risk they can’t take on new debt, or if they can, it’s very expensive. Not being able to borrow what they need to run the economy, will cause a major slowdown of the economy, or said in terms that focus more on human consequences, it will cause vastly increased poverty in Pakistan, because any crisis always hit the poor the hardest.