Current Supreme Court precedent holds that a retailer must have a physical presence in a state before sales tax can be charged on its interstate sales into that state. This seems both sound law and economically reasonable in that such sales do not provoke a need for government services that a retailer’s physical presence evokes. My guess is that the Court will again follow this rule and emphasize that Congress can use its commerce power to change it if they wish. In other words, the people’s elected representatives should make the final and binding decision on the issue.
I agree with your analysis. Unless there is a physical presence, the state is providing nothing to the retailer, and thus has no basis for collecting any tax. The moment there is a physical presence, they are providing police protection, fire protection and the ability to use the courts. Those things mean that the state is providing some benefit to the retailer, even if it is only the psychological benefit of knowing that such things exist and could potentially help the retailer, so the state thus deserves some return for what it is providing. Otherwise, no dice.
In 2016, SCOTUS allowed Colorado’s Amazon tax to stand. Online retailers can either collect sales tax or keep records of customers’ purchases and file reports on each customer at the end of the year, along with providing the customers with tax reports if they’ve spent over $500.