[jasongi]

This is the confusing thing, the way it is described is like a hybrid of government welfare and a defined-benefit pension.

How can you simultaneously be "paying into" social security but also have describe it as current workers paying for current retirees?

The only way you really find out which one it is is what happens when it runs out of money - if the government backs it up to give you the full "entitlement" you paid into it, then you were in-fact "paying into it". But if they don't, or change the rules then it sounds like you were just being taxed.