My opinion is firm: the state and local tax deduction (SALT for short) is bad.
Because it’s equivalent to that the federal government takes money from the people in Utah and Washington and gives it to the people in California and New York, merely as the consequence of that the people in California and New York voted to give more money to their state and local governments.
Generally speaking, I am against that A decides B should give money to C. Sometimes such redistribution is justifiable, for example, when B is rich and C is poor. However, when it comes to the state and local tax deduction, it’s the other way around. The federal government is taking money from the people in Washington and Utah, including the poor ones, and giving it to the people in California and New York, including the rich ones. It's transferring money from the poor to the rich. Even liberals should be against such reverse wealth redistribution too.
Another reason why I am against the state and local tax deduction is that it’s encouraging a behavior that, in my opinion, the federal government should remain neutral about. The state and local tax deduction is encouraging state and local government spending. There are people for it and there are people against it. Nevertheless, the federal government, in my opinion, should not take a position on this matter, as it's a matter of the state and local governments.