Oh, and, by the way, the dollar is scarce. The amount of dollars in circulation is not infinite. And we could say it is somewhat backed by gold. There is gold in their vaults. It is even redeemable for gold; you can buy gold with it or sell gold and receive dollars. It is not redeemable for a fixed amount of gold at the federal reserve or the treasury, however, but that's just a technicality. Don't worry about it. Everything is fine, isn't it?

See how I can troll if I set myself to it? :)