But we did have national debt before 1913. And in fact it grew exponentially during the Civil War, as it has grown exponentially during any military conflict. In fact every year between 1900 and 1913 had a gradual increase in the amount of debt, jumping during WW1, jumping again during WW2, jumping again during Dubya's wars - all the while gradually increasing between major conflicts.

You're looking to "The Fed" as the reason why our debt has grown out of control, but in reality the trend started before it was in place. As far as I can tell, all it was intended to do was protect banks against problems they'd experienced rather regularly up until that point. It wasn't intended to prevent the creation of more and more debt. The real reason for the debt being what it is today is all the wars we get into.

Ironically WW2 was credited with ended the depression and stabilizing our economy, but the national debt increased by around 373%, from $72B to $269B. WW2 didn't stabilize our economy; the government putting almost $200B into it did, in order to manufacture war materials. And it's really no surprise the constant rate of increase has itself increased since the dawn of the 20th century. Ever since WW1 we've been in one international conflict after another. It costs money to build and maintain a hegemony, and the government has become accustom to borrowing that, always thinking to themselves it'll pay off. It never does. Buy gas lately?