You are wrong about point number 1. The purpose of mining is to process and secure bitcoin transactions. The work that goes into mining is what provides the utility of bitcoin. The 25 btc mining reward is just an incentive.
Re:BTC correction happening?
by betterunix on Tuesday November 19, 2013 @06:57AM
(#6760546)
The problem with your theory is that it permits anyone to start their own Bitcoin fork and magically people will use it.
2. USD is backed by the law -- laws concerning debts, laws concerning taxes, laws concerning torts, etc. The law is what makes USD useful, which is why USD has value.