In 1913 when the Federal Reserve was created, the US began to borrow our national currency from this new corporation of international bankers and so begins to owe interest on our own money. A really bizarre twist!
The following refers to what happened next. I'm not sure how factual it is but it certainly makes sense and would explain a lot. It is an excerpt from http://www.nomoreserfs.com/notice_to_public_servants.htm :
From 1913 until 1933, the United States paid the “interest” with more and more gold. The structured inevitability soon transpired: the Treasury was empty, the debt was greater than ever, and the United States declared bankruptcy. In exchange for using notes belonging to bankers who create them out of nothing on our own credit, we are forced to repay in substance (labor, property, land, businesses, resources - life) in ever-increasing amounts. This may be the greatest heist and fraud of all time.