Behind a Veil of Ignorance

So, as per usual, I've been translating wikipedia articles into English, and I've been learning about John Rawls. So far he seems awesome (but dead).

Those of you who adore The West Wing may recall that the less-handsome replacement for Sam Seaborne mentioned to his unpaid, inexperienced writing staff something about a "veil of ignorance".

John Rawls came up with that.

Essentially, the principles and laws for a just society should be constructed from The Original Position, behind a Veil of Ignorance. Everyone would naturally want to set up a system where the king gets everything and then make himself the king. But the original position and veil of ignorance say that you don't know what position you'd be born into. You don't know your social class or economic status. You don't know what sort of abilities or talents you might have. You don't get to choose to be king.

Rawls argues that, from behind the veil of ignorance, everyone would instead set up a fair society based on two principles:

1) Everyone has access to the same extensive liberty, with that liberty being conditional on everyone else also having access to that liberty (that is to say, rights and liberties will always come into conflict and have to be balanced).
2) a) Any inequalities must be structured to give the greatest benefit to the least advantaged. (the principle of difference; for example, progressive income tax at the higher income brackets balanced with a negative income tax [or a tax credit] at the lowest brackets)
2) b) Everyone must have access to positions, offices, and opportunities (equality of opportunity)

Legislators and others in power should be guided by the original position and veil of ignorance in that they should set aside their own positions and privileges and structure society so as to accrue the greatest benefit to the least advantaged.

This just seems so darn sensible. How is it that not everyone is a socialist?