Two things worth noting here:
- First, it's more honest, because FICA has never been anything other than a tax, considering that the federal government has always spent the revenues that it has received from FICA, pretty much on the spot. There's no lockbox or big vault that the feds keep your money in. They will (or might, depending on how old you are) pay you Social Security from whatever is available at the time you are allowed to collect it. And if the dollar happens to have the same valuation as a Turkish lira, tough luck, pally.
- There's a larger purpose afoot in identifying FICA as a tax, though. In recent years Republicans have argued, often successfully, that nearly half of Americans don't pay income taxes. Because of the large income deductions that are in place, that has been true, but I've always thought that it was misleading, because nearly every American who files a W-4 form gets nicked for FICA, which does take essentially 13% of your income off the top. That's why the temporary rollback of FICA rates for this year can be called a "middle class tax cut." And in doing so, it allows those who love government to challenge the notion that nearly half of all Americans don't pay income taxes.