Which since sales taxes are imposed on the Merchant (although he certainly can and often does pass them on to the purchaser) made them UnConsitutional.
No, interstate sales taxes are not unconstitutional. Forcing a merchant to remit sales tax to a state where they don’t have a physical presence is unconstitutional. The distinction is critical.
Four situations:
(1) LL Bean in Maine sells and ships to me in Illinois. Illinois demands that Bean remit sales tax. An interstate sales tax, but unconstitutional because Bean has no stores in Illinois.
(2) Sears Catalog in Wisconsin sells and ships to me in Illinois. Illinois demands that Sears remit sales tax. An interstate sales tax, and perfectly constitutional and enforceable. Sears has stores in Illinois.
(3) LL Bean in Maine sells and ships to me in Illinois. Illinois demands that I remit sales tax, since they can’t collect from Bean. An interstate sales tax, and perfectly constitutional. In practice, Illinois may have difficulty in enforcing this if I choose not to pay.
(4) I drive up to Sears catalog warehouse in Wisconsin, make a purchase and bring it back to Illinois. Illinois demands that I remit use tax. Perfectly constitutional, although again difficult to enforce. In your first post, you said that calling this a “use tax” is a “duck” to make it constitutional. It isn’t. As we saw in Case (2), this was already constitutional even as a sales tax. Calling it a “use tax” merely recognizes the fact that no sale took place in Illinois.
mks57–yes, discriminatory interstate sales taxes are unconstitutional. That is a special case.