My concern is that it could be slipped in under cover of an emergency. I referenced 9/11 and how it opened the door to massive increases in government surveillance over private citizens. I can easily foresee an "emergency" need for immediate government revenue, say if our ability to borrow is compromised by a big credit rating loss, China and Japan refuse to buy our bonds anymore, the wealthy have already moved their money out of reach and a war breaks out. All of a sudden, that limit drops and trillions of dollars are sucked out of the economy, straight out of the middle class. And, once that's done, who imagines that it will ever revert back to "normal" again? In this reality, we HAVE to consider worst case scenarios, because the restrictions of the past are being removed.True. But with something 7.8 trillion dollars in 401ks, its not inconceivable that a tax on unrealized gains would be applied to them as well.
Its unrealistic, unlikely, and politically unsound. But not inconceivable.