The total amount of money owed to lenders by the us government is

I believe the answer is: national debts

The national debt  usually amassed by the government during inflation period or during the effort to develop infrastructure.

To maintain the strength of currency, the government sold Government Bonds to the public in order to reduce the amount of dollar circulated in the market. The national debt also could be incurred when the government obtain the debt from other countries for our own countries' development.

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