That’s a tough question, Sip(addressing your second to last post...haven't read your latest yet. I will). I think that the social security and medicare taxes are just taxes. They are not in a lockbox, they are not earmarked for benefits, and you do not "get back the money you paid" when you start drawing ss or medicare.
This fiction is engaged in equally by Democrats and Republicans when it suits their purposes, and it is eagerly seized upon by the elderly, who see everyone else who gets benefits as living off the government tit, "but they paid for theirs". All tax money goes to the same general revenue funds, and used to pay the obligations of the US, including ss and medicare. Future taxpayers will pay your social security benefits, just as I am paying the benefits for current recipients.
I am ok with that. In the years when they ran a surplus, this was great. During the coming/already hitting baby boom lump in the snake, this will be a problem.
Income taxes and payroll taxes are separately provided for in the tax code (in part) to facilitate application of these reductions to income tax, and to facilitate collection of the employer's contribution to payroll taxes (I think the calculation is different for medicare and ss), but the distinction between payroll and income taxes is largely an artifact of accounting requirements - taxes are taxes.
I think great mischief has transpired as a result of pretending that these taxes are not taxes to pay obligations of the government, but a trust fund. The Democrats are primarily responsible for the popularity of this fiction. Rather than defend the social security system on its merits, they scream "lockbox." Of course they also engage in this fiction, in part, to defend against screams from the Republicans of "socialism!”
Because of how I view those taxes, you are right. I don’t like to discuss income tax rates in isolation from payroll taxes, because they are not paid in isolation. But I get your point, so I'll try. If I were to revamp the system, my changes would not be very popular. I'm on the fence about removing the payroll tax cap. On FIT, I would make all income subject to the same tax rates, including capital gains. I would, however, define capital gains income to exclude gains due to inflation (warning: this opens a pandora’s box of creditable claims of other incomes and deductions that should arguably be inflation adjusted, such as real versus nominal interest payment deductions. Full adjustment of the code for inflation is an impossible task. I just think it’s justified for capital gains, new market distortions notwithstanding-but I could be wrong. This also complicates tax calculation immensely. So much for simplification.).
I think most exemptions and deductions designed to influence behavior are a bad idea, though we are irretrievably addicted to many of them (e.g.- home mortgage deduction, active/passive interest special rules for Oil & Gas drillers, intangible drilling cost and intangible drilling cost exemptions, and a passel of other O&G special benefits, the entire tax benefit structure that created a wind energy program that is not ready to stand on its own, and many others). I admit that I may be wrong on some or all of those I’ve listed, and the problem is horribly complicated, and some behavior modification through taxation is probably inevitable. (example, should we create tax disincentives to exporting jobs? How? What about excessive executive compensation? Should huge salaries be fully deductible as a business expense? How do we know when “salary” is really a disguised distribution of profits? What about helping vital American industries that face unfair competition from mixed economy foreign competitors? I don’t pretend to have an answer or a coherent overall theory for evaluating same. I also assert that you (not you personally, Sip, but a more generic you) pro business types who leap to the defense of just about any tax break that benefits business, the owners thereof, and the energy industry do not have a coherent overall theory either. This stuff is not as easy as partisans on either side (more properly “any side”) pretend that it is.
An honest discussion and overhaul of corporate tax rates would be a great thing too, but who knows if it will happen. Conservatives are correct that nominal corporate rates are too high in the US. Liberals are also correct that corporations make out like bandits using tax code manipulations, and only suckers pay those nominal rates. Once again, when I look at proposed solutions, I see that it is not so simple to fix. Lowering nominal rates cannot be done responsibly without fixing the gameability (if that’s a word) of the code. That will be a nightmare after decades of accreted rules, many put there for a good reason, many as a sop to the corporate benefactors of politicians. I wish I knew a responsible, simple way to fix it. And no, I don’t think “9.9.9” or the cleverly but not so accurately named “fair tax” is it. (I’m too tired to argue with you Bortz listeners, I get your arguments, just don’t buy them). Rebooting the system and starting from scratch is a non starter, IMO. Simple sounding, but catastrophic unintended consequences.
All the crap above really means, Sip, that I don’t really have a clue. Mainly, I just think we have a better chance of achieving beneficial reform, not just reform so we can say we did it, when we are honest in debate. The simple solutions of partisans on all sides are usually not honestly presented, again just my humble, and probably wrong opinion. Useless, huh? but you asked.