Richard Phillips wrote, in response to my suggestion that a state income tax would have the advantage of getting revenue from those who live out of state but work here, "The courts already ruled against taxing out of state residents."

This is completely wrong. There are many people who live in one state and work in another. If both states have an income tax, then taxes are paid to both states—to simplify somewhat, the state where the individual works but doesn't live is entitled to tax on only the income earned in that state, while the state of residence is entitled to tax on all income earned, but with a credit for income tax paid to other states.

Yes, it can get complicated, but it's a pretty common situation (just look at how many people live in New Jersey or Connecticut but work in New York City, for one example). There is no basis to a claim that out of state residents wouldn't be subject to income taxes here.