"by the right of the nineteenth ammendment (I think that's the one) that authorized the income tax to begin with. And if you think that you can change it without another constitutional ammendment, then you will find out to your loss that we will then have TWO tax drains - income AND outgo."
Nothing prevents them from implementing both systems today, however the way the legislation is written it would protect us from having both systems.
you cannot pass a law that changes the constitution. that requires an ammendment.
until and unless the income tax ammendment is aboliched (which may take years, 2/3 states, etc..) don't expect this pollack to sign onto ANY new tax proposal.
at least mine stays within the confines of the constitution (AFAIK) and would not require an ammendment.