A specious argument -- the Fair Tax is not touted as solution to the Social Security problem by anyone, it simply replaces the collection method. Fixing Social Security is a separate problem -- and no proposed alternative to the Income Tax proposes a fix to Social Security.
If you want to argue that Social Security is broken and desperately in need of a drastic solution, I'll completely agree with you, but to use that as an argument against a taxation strategy is absurd -- the two have nothing whatsoever to do with each other.
Patently false. The "underground economy" referred to is illegal activities. Under the Fair Tax, every dollar spent that was earned illegally will be taxed at the point of sale. When a drug dealer buys his Lexus, he'll be coughing up 23%. What you're referring to is the supposition that the Fair Tax will suddenly result in massive amounts of under the table sales in order to avoid the tax -- what you're argument fails to consider is the massive infrastructure necessary to support the sale of products in that manner. Sure, there will be "cash" sales of goods and services that stay off the books -- much as there are today in order to avoid the income tax -- but to have any significant impact would require massive "underground" markets. If someone opens a secret Best Buy out of their garage, I think it would be noticed.
There's a huge difference in manpower and power of an agency needed to support a sales tax vs. income tax. Look at the tax enforcement agencies of States with only a sales tax vs. those with an income tax. The IRS elimination means that the days of individual Americans having to file on April 15th, having to keep records all year, having to fill out forms, having to call the IRS with questions that 50% of the time are answered wrong, of individual Americans having to face the full police powers of government in an audit -- are gone.
Oh, my god! You're right -- keep taking that $1000 a month FICA from me, 'cause I don't want to pay an extra penny on my stamps!
I ask: "So what?"
A very small percentage of Americans who make less than the Poverty Index will receive a very small amount more in the prebate than they pay out in taxes. Even as a pretty hardcore Capitalist, I'm okay with a family of four living on poverty-level income paying no taxes. I'm okay with that family even getting a little extra out of the prebate. Precisely because the poor spend a higher percentage of their income on retail goods and services -- if it were simply a consumption tax without the prebate, then it would place a disproportionately high burden on the poor.
Under the Fair Tax, the poorest Americans are exempted from taxation and the the tax burden is based on how much you spend.