No. of Recommendations: 4
Moving goal posts alert, Batman! :)
How is that moving the goal posts? FICA is part of the tax code, and is just as much a federal tax as the income tax. And part of the reason we don't require everyone to pay non-trivial amounts of federal income tax is because we have a system of government where states are separate sovereign entities that provide a lot of services, that get paid for through regressive forms of taxation like sales and property taxes. Which taxes, BTW, are also reflected in the U.S. tax code.
If you have multiple taxing entities, you'll get bad policy answers if you look at separate taxes entirely in isolation, rather than considering taxation systems as a whole.