This statement was in the original OP and a recent post [Note: The word "to" was added after "seem" below.]:
"Fair would seem to be that the group of taxpayers who earn 10% of the country's income would pay 10% of the country's taxes; the group who earned 20% would pay 20% of the taxes and so on. "
I don't agree with this statement, although I do agree with the sentiment that the rich are paying more than their fair share. Fair would be an equal payment made by all who share in the services provided. Many are too conditioned by years of looking at tax rates and what percentage of income someone pays to comprehend what constitutes "fair." For those interested, here is what's fair:
Who pays their fair share of Federal taxes US Message Board - Political Discussion Forum
Making people who earn more pay more in absolute dollars is passive robbery. Because you've been robbed though a seemingly democratic process doesn't make it less wrong. Why is our tax system like this? It's practical. Money can only come from those who have it.
Full disclosure: I pay less than my fair share of taxes. But I'm honest enough to say, "Thank you!" to those who pay much more than their fair share instead of clamoring for them to pay more.