States not having jurisdiction outside of their borders isn't exactly a loophole. If California wants to punish people for buying from Oregon, a state free from sales taxes, it should use its existing use tax and take it up with its own citizens. This ruling is saying that California can tell Oregon businesses what to do.

Sure, but there's no point in getting bogged down in strict adherence to jurisdiction when we're all one country. Would you feel better if the ruling was that an online retailer in Oregon has to get a business license in every state which would come with the same requirement to collect sales tax? Same effect, but now businesses have to do more paperwork.

If we're all one country, how did the President get elected when the majority of the country voted for someone else?

..and yes, I'd prefer that the ruling was that the online retailer had to get a business license in every state. That ruling would create such a torches and pitchforks situation from citizens suddenly having their lives disrupted that we'd quickly return to status quo.

I mean even if we lived under a monarchy we would still be one country, the two things aren't really related.

That is the worst possible reason to enact a law. It should be obvious why making people's lives worse purposefully for political posturing is a bad idea, and you run the risk of your plan backfiring and having to live forever in the now-worse world.

This isn't enacting a law, though. This is changing the interpretation of the constitution. Prior to this, the interpretation was that the framers' intent was for citizens to be governed by the laws of their own state, now it's not. Let the chips fall where they may.

I don't think the distinction between legislative and common law is really meaningful in this case. A judge making a decision in a case like this is bringing a new law into existence.

Suppose I the owner of a small retailer based out of Oregon but have a location in Ohio. Should I be exempt from collecting sales tax simply because my company is registered and HQ'd in Oregon? The previous ruling was no, Ohio has the right to require my company to collect sales tax for sales in Ohio, but the ruling required that my company have a physical presence in the state. All that happened today was that the requirement to be physically present was dropped.

I mean the law is fairly narrowly scoped and certainly doesn't give states a blank check to write laws for citizens of other states.

Interesting. One thing I've noticed is that certain on-line sellers exempt purchases to certain states. I wonder how long before they start exempting residents of states that force online sales tax collection.