Interesting editorial in today’s Wall Street Journal:  The Top 1% Pay 35%:

Maybe our liberal friends are onto something. They keep saying the rich should pay more taxes, and it turns out the rich already are! That’s one of the valuable lessons from the IRS’s annual study of income tax data, just released for 2004. Americans who earned more than $1 million in adjusted gross income paid $178 billion, or an average of $740,000 per filer, in income taxes in 2004. That’s up about one-third from 2002, the year before the Bush tax cuts in marginal income-tax and dividend and capital gains rates. The wealthiest 1% of tax filers paid a remarkable 35% of all individual income-tax payments that year….

This is by any definition a "progressive" tax system. Make that highly progressive.