we ain't seen nothin yet if that comes to pass.
There has never been a question of whether states can charge sales tax on internet sales. States with an income tax have had a line to self report internet purchases and pay the sales tax when filing.
The bone of contention is with those states without an income tax. They have to rely on individual internet companies charging and collecting sales tax on behalf of the state, and forwarding that revenue to the state.
The point of litigation is can a state compel a company with no physical presence in a particular state to collect and remit sales tax for that state.
This is a question of regulating interstate commerce, and is a Federal question, and barring any federal laws requiring reciprocity of sales tax collection among the several states, my answer is ‘no, you cannot compel an out of state entity to collect and remit sales taxes to the state.’
The People’s Republic of MD already does it!