California provides an object lesson in why steep progressive tax rates are a bad idea. The state is awash in cash in boom years, and when recessions hit, the funds don’t just shrink. They dry up.

Of course, this is exacerbated by the fact that during the boom years, the politicians shower rich, greedy public employees with payroll, pension, and pork that no state or nation can sustain.

If Obama succeeds in his tax hikes on “the rich,” he will only make matters worse.

Rise of the Super-Rich Hits a Sobering Wall

The relative struggles of the rich may elicit little sympathy from less well-off families who are dealing with the effects of the worst recession in a generation. But the change does raise several broader economic questions. Among them is whether harder times for the rich will ultimately benefit the middle class and the poor, given that the huge recent increase in top incomes coincided with slow income growth for almost every other group. In blunter terms, the question is whether the better metaphor for the economy is a rising tide that can lift all boats — or a zero-sum game.

Only an idiot thinks it is a “zero-sum” game. Language deficiencies or not, at least Bush understood that we have “grow the pie higher.”

Some economists say they believe that the contrasting trends are unrelated. If anything, these economists say, any problems the wealthy have will trickle down, in the form of less charitable giving and less consumer spending. Over the last century, the worst years for the rich were the early 1930s, the heart of the Great Depression.

Other economists say the recent explosion of incomes at the top did hurt everyone else, by concentrating economic and political power among a relatively small group.

“I think incredibly high incomes can have a pernicious effect on the polity and the economy,” said Lawrence Katz, a Harvard economist. Much of the growth of high-end incomes stemmed from market forces, like technological innovation, Mr. Katz said. But a significant amount also stemmed from the wealthy’s newfound ability to win favorable government contracts, low tax rates and weak financial regulation, he added.

You don’t do that by allowing the rich to game the system, but you don’t do it by taxing them too much either. The rich will always find a way to avoid the worst taxes. Only an idiot works to punish them.

In the three decades after World War II, when the incomes of the rich grew more slowly than those of the middle class, the top marginal rate ranged from 70 to 91 percent. Mr. Piketty, one of the economists who analyzed the I.R.S. data, argues that these high rates did not affect merely post-tax income. They also helped hold down the pretax incomes of the wealthy, he says, by giving them less incentive to make many millions of dollars.

Since 1980, tax rates on the affluent have fallen more than rates on any other group; this year, the top marginal rate is 35 percent. President Obama has proposed raising it to 39 percent and has said he would consider a surtax on families making more than $1 million a year, which could push the top rate above 40 percent.

What any policy changes will mean for the nonwealthy remains unclear. There have certainly been periods when the rich, the middle class and the poor all have done well (like the late 1990s), as well as periods when all have done poorly (like the last year). For much of the 1950s, ’60s and ’70s, both the middle class and the wealthy received raises that outpaced inflation.

Yet there is also a reason to think that the incomes of the wealthy could potentially have a bigger impact on others than in the past: as a share of the economy, they are vastly larger than they once were.

In 2007, the top one ten-thousandth of households took home 6 percent of the nation’s income, up from 0.9 percent in 1977. It was the highest such level since at least 1913, the first year for which the I.R.S. has data.

The top 1 percent of earners took home 23.5 percent of income, up from 9 percent three decades earlier.

If it appears that I’m overusing the word “idiot,” blame the article. Who thinks like this?

In the three decades after World War II, when the incomes of the rich grew more slowly than those of the middle class, the top marginal rate ranged from 70 to 91 percent. Mr. Piketty, one of the economists who analyzed the I.R.S. data, argues that these high rates did not affect merely post-tax income. They also helped hold down the pretax incomes of the wealthy, he says, by giving them less incentive to make many millions of dollars.

Why on earth would you want to destroy the incentive to earn more? No one is arguing for letting the rich game the entire society in their favor (something Democrats allow as much as Republicans), but the fact is that the more rich you have, the more money you have for necessary government services. (and fat pensions and early retirement aren’t necessary)

The best tax system is one that taxes many things, all at very low rates. This isn’t rocket science.