Raising taxes on the rich doesn't make the tax system more fair. It makes it more punitive. In the end, most Oklahomans have a sense of how much government they think they need and how much of a sacrifice they're willing to make to pay for it. This may help explain why there was no groundswell for a state income tax cut in Oklahoma last year.
The federal scenario is different: The Bush-era tax cuts benefitted far more than “the rich” and the definition of “rich” is quite elastic.
Justifying a federal tax increase based on fairness is bogus. A truly fair system would tax every income level at the same rate. Justifying a tax increase based on the need to bring in more federal revenue is folly. It would lead to even more unsustainable spending levels.
So what's left in the tax-hike justification arsenal? Nothing but this: Envy of the very small group of people paying a very large share of the taxes.