U.S. Public Debt Since 1940

Here is the U.S. public debt since 1940:
In the first 200 years of U.S. history, the total net amount of money borrowed by the government was less than $1 trillion.
In the subsequent 33 years, government borrowing increased the debt by more than $10 trillion. There was relatively little debt prior to 1940. Government borrowing increased significantly in the 1940s to finance U.S. expenses related to World War II.

See also the "U.S. Public Debt Since 1940 - Adjusted for Inflation" and "U.S. Public Debt as a Percentage of Gross Domestic Product (GDP)".