[T]he way fractional reserve banking in general and the Federal Reserve in particular is set up, there is always more debt built into the system than there are dollars in circulation. That's because debt is attached to money the moment it is created; i.e. for every X dollars in circulation there is always X+Y debt. This system is just not sustainable. How could it ever do anything but ultimately fail?
Dear Parent, I presume you understand the fractional reserve system so you can skip down to paragraph 4 whilst I provide an Economics 101 refresher for the gallery (and this really is first-semester stuff; I taught it earlier this year):
You and all your friends deposit money at the bank. The bank holds a fraction of the money in reserve (hence the name), at minimum the amount the law specifies, usually plus some amount X. We'll come back to this. The rest of the money it lends to people who want to borrow it; they pay interest, you get interest, the bank takes a cut, hooray.
These borrowers spend the money, and the people who get it stick some of it back into the bank, where the cycle starts afresh. It depends on how much money the bank holds in reserve and how much the populace deposits but, yes, usually there is more debt around than originally produced currency.
Now, you claim that this is a Bad Thing (TM). You don't state why. Presumably you are relying on the intuitive logic that having more debt than official assets can't be good. That intuition relies on the following crucial point: having more debts than assets is only a problem when people try and collect on their debts. Amazingly, this very rarely happens.
You have the absolute right to go to the bank and demand your money, in bar. All of it. Buy who does that? Practically no-one. You ask for a portion of it; some here, some there, more at Christmastime and during the holidays. So long as the banks have enough money to give everyone what they want – and this is the amount X from above – holding the rest of it would just be inefficient, since none of the depositors want it and there are plenty of borrowers who can do productive things with it. Fact: if the banks decided to hold more money in reserve, the government/central bank would simply create more 'original' dollars until the effective level of money is back where it was.
The fractional reserve system does have its problems. But the problems lie in deciding how high the reserves should be – too low, and when people do decide they want their money everything comes crashing down (e.g. AIG). Too high, and businesses can't borrow money and productive potential lies wasted (e.g. the current situation in much of Europe and the US).
But the system is not inherently flawed. If the right level of reserves are held – and this is usually the case – the system provides a much more flexible and efficient supply of money than a representative currency.