That is a very well-reasoned explanation of your stance, thank you.
Personally, I oppose a national sales tax because I believe that it would stifle spending. I would prefer a national income tax but no state income tax. States could generate their income from sales and townships from property.
My follow-up questions for you are what, if any, role do you see for the government in providing financial aid for those who are genuinely unable to provide for themselves? Do you think that with a lower tax burden from eliminating social welfare programs there would be more money available for charity? Also, what is your opinion on a flat negative income tax as a replacement for social welfare programs?
Private charity is more than up to the task of taking care of those who truly cannot do for themselves. As I wrote previously, government doesn't do charity because charity is voluntary, not compelled. It is the least efficient way to get help to people who need it, and worse, what government "charity" does to its recipients in a metaphysical sense.
Not advocating for a return to Jim Crow at all, but in spite of Jim Crow, black people made continuous economic advances, improving their lives. That largely ground to a halt with the Civil Rights Act of '64. Prior to that, white and black literacy, numeracy, and bastardy rates were about the same. Most black kids grew up in 2 parent homes and were better off for it. Read anything by the late Walter Williams or Thomas Sowell on the value they obtained from that.
As to national sales tax...
prices wouldn't be hugely different than they are now, but the lie would be put to the government's story about soaking the rich and big business with high tax rates. And the reason is a simple economic reason - prices on goods and services will fall in the absence of businesses passing on their costs of compliance and actual tax owed to their customers.
If you go to the grocery and spend $100 right now, probably $25 of that pays the tax bill all the way up the supply chain. That sounds like a pretty good windfall if that $25 stays in the pockets of the business owners, but it will not, at least not for all of them. If I'm a competitor in the national grocery market, I seize the opportunity to drop my prices by 25% and increase my market share. The other grocery chains would need to follow suit. So on that $100, I also pay local sales tax. I'm paying a tax on a quarter of my bill which was also tax.
So assume your grocery tab is now $75, and that gets the exact same quantity of stuff $100 previously. Well, let's suppose a national sales tax of 25%. - that brings up your total bill to $93.75, still $6.25 cheaper than it was before.
Bear in mind that not a small portion of the income tax bill all the way up the supply chain isn't merely what's remitted to the government, it is in large measure a cost-of-compliance issue as well. Under the old system, the federal government never collected that 25%, it only collected a portion of it.
There are some who would suggest we go to a flat income tax. The problem with that theory is that we already had that - and when the 16th amendment was ratified, the only people who paid any income tax were those who earned money from rents, dividends, and the like. And the threshold was, I believe, $500,000 in annual income. Of note is that remuneration for services rendered (aka "employment") was not taxed.
The 80K page obscenity we have now grew out of that very simple tax. Any "new" flat tax will do the same.
Government "service" always comes at significant cost, and relative to disposable income, the cost of government is born most heavily by the people who can least afford it, not "the rich," however that term may be defined.