I've mentioned before that one of the cards I leave in coffee shops says, "Is there such a thing as a moral tax policy?" The point of the cards, titled Discussion Starters, is to present something neutrally to allow discussion. And, like all of the questions, I do not have a fully formed opinion.
Here's something from MoveOn.org.
"The share of after-tax income going to the top one percent rose from 12.2 percent in 2003 to 14.0 percent in 2004," making that the largest one-year increase in the share of income going to the top one percent in 15 years.
MoveOn has an agenda, but I selected this statistic because I think it is helpful. (Cf. comparing Dick Cheney's tax savings to the average person in the bottom 20%, which is a completely unhelpful statistic.)
Here's what I think about this as a modern Christian. Concentration of wealth makes me uneasy because I don't like concentration of power. But, as far as people with million dollar incomes keeping a bigger share of the pie than people with $100,000 incomes, I'm not sure I can become too upset with that. And, I think that is what is driving the statistic. In fact, much of that change is the result of the Alternative Minimum Tax affecting more people, which would case just this result for just this reason.
As a Christian, I don't want to see funding the government to be an undue burden on someone struggling to survive. I need to not have people going without necessities of living (for sure), and (I think) health care or education in order to pay their tax bills. I don't think that is happening now. So, I think we have a moral tax system.
This is a good example of a matter for which I have opinions that are entirely unrelated to my moral opinions. For example, I think the economy functions better when the tax system prevent money from pooling in the hands of a few. When you spread out wealth, you have more transaction/spending. And, that is the engine that drives our economy. For that reason, I believe our tax rates should be more progressive. But that is the ramblings of a non-economics trained liberal. It has little to do with economics and nothing to do with morality.