>> “ as a general principle, on-line retailers should be subject to the same taxes as local bricks & mortar retailers” <<
Nonsense!
Locals have the ability to affect the politics of the state; out of state sellers do not.
States are constitutionally prohibited from tampering with interstate commerce, so it would require an amendment of the constitution to legitimately open this insane floodgate.
Congress is not constitutionally empowered to extend to the states the power to tax interstate commerce either.
I can’t dispute what you say regarding the Constitutional issues (I plead ignorance). My remarks are entirely based on time-tested principles of tax policy.