Why was the national government unable to solve its financial problems?

The U.S. cant solve its financial problems because there is a deficit in their budget.
This means that The U.S. spends more money than it earns, every year.

The sad part is that the Federal Reserve (private corporation, not related to any government or federal entity) who "loans" our government money, knows the governments budget and they also know that there's no way it will be returned in full.. Yet they still loan them the money. Do you see the problem here?

They made a checks and balance system to equal power within the branches. the "check" meant that one branch would watch one branch and "balance" them if they were too powerful. if you want more info on this, i would just google checks and balance system.