"A 5% revenue tax on the fortune 500 would get us half way there."Given that ~20% of that group have net income margins below 5%, how much of such a tax policy would simply be an inflationary tax on consumers? I.e., we know Walmart cannot simply pay a 5% revenue tax, that would instantly make them deeply unprofitable. So they would have to raise prices to afford the tax. And if they know Target, Kroger, Costco, and Amazon also need to pay the same 5% tax, there is less competitive pressure to eat into margin. Even with zero collusion, there is perfect information symmetry regarding the tax.
At their present 3.1% net margin, if Walmart passed a 5% gross-revenue tax entirely to consumers while all else stayed equal, prices would have to rise MORE than 5% -- about 5.44% just to preserve its existing margin. Of course, some of the tax burden likely gets shared between Walmart, its customers, supply chain, vendors etc... In a world where the Fortune 500 (Walmart) has to pay the 5% revenue tax but a supplier of some SKU (not a Fortune 500) does not pay it, I imagine Walmart would lean extra hard on them to eat some of the tax. It all seems like a very messy and inefficient tax.
On the VAT, the CBO has actually studied a 5% VAT tax and modeled that it would raise $330B. That's 16% of the current $2.1T deficit.
https://www.cbo.gov/budget-options/58637