Why is counterfeiting money wrong?

I am looking for an explanation that doesn't apply generally to copyright, trademark, and patent infringement. I do not consider "intellectual property" to be a valid concept and I would like an explanation that does not invoke it. In other words, can you outline a world view in which photocopying a book is permitted, copying a CD and giving it to your friends is permitted, but counterfeiting money is still a big no-no?

This one is practical: you would be gaining money the government cant afford to pay you. You would be claiming to have money that the government doesn't have record of, and that would be a national incident. If you were to buy something with fake money,you would be stealing from the person who is paid with it. When they turn it into the bank and get arrested, it isn't very fun for them.

Only our government is allowed to print money and not have the funds to back it up.

Every dollar that is printed is backed by the Federal Government. If people just randomly printed their own money, we would have a huge issue with our economy

Because you're shorting the government money. You have created a peice of paper that says that the government is supposed to have, say, $20 worth of gold in their banks, however when people create their own money, they're representing money that the government does not have. That's why it's innately wrong to create tender that is not represented by the government's bank.
Photocopying entire books and copying a CD and SELLING it are also big no-nos, but harder to catch. The government can catch you using a fradulent bill very easily, that's why it just seems like a bigger offence.

Counterfeiting is like stealing. It takes away the value of actual money, and hurts the national economy. Besides, counterfeiting often goes hand in hand with other serious crimes- drug smuggling, gun running...

If you are counterfeiting or know someone who is, I would strongly advise you to stop. Not only is it hard, but its a federal crime. And I think the last thing you would want is the US Secret Service knocking on your door with a warrant and a pair of handcuffs.