They already are, but in the USA, they have a better, time proven method.
Inflation. In this case, it may develop into hyperinflation.
In Cyprus, they will steal the actual banknotes from depositors. They will let you keep the banknotes in the USA, but are stealing the value instead. Same thing really... you will be left with just the 'wrappers' for your money.
Just like in 1965 when they took 50% of the silver out of the coinage and in 1969 when they took the rest of the silver out... you are left with the 'bottle' that the silver once came in.
Your currency is now just the wrapper that once contained money.
In Cyprus, they took away your money - but at least it was honest.
In the USA, you will still have the banknotes, but they will be worth about the same as what a Cypriot has when this is finally over.
That is the road we are being led down.