Of course he is drastically oversimplifying the situation, but he is referring to the fact that when our government takes on a debt and promises to pay it, it is the productivity of the citizens that ultimately pays that debt. The government takes what it needs from the citizens by way of taxation, and by printing more money (Federal Reserve) which causes inflation and devalues the money that we already have. So we are working hard but the fruits of our labor go abroad by way of our government's debts, incurred largely by fighting in wars. Does that make more sense?