All of which is a vastly different beast from raising taxes on high income earners from 35% to 39.6%.

So with today's economy teetering at the edge of a second recession, why is President Obama so determined to let the Bush tax cuts expire on top earners at the end of the year, effectively raising their taxes? And why do Republicans seem willing to go along with the idea? Here are five reasons:

The proposed tax hikes would affect relatively few people. Obama wants to extend the Bush tax cuts for most workers, which means that for individuals earning less than $200,000 and couples earning less than $250,000, nothing would change. That accounts for nearly 97 percent of all taxpayers. For the other 3 percent, Obama would let tax cuts expire, which means the top tax bracket would rise from 35 percent to 39.5 percent, and the one below that would rise from 33 percent to 36 percent. Dividend and estate taxes would also rise, but those mostly affect the wealthy. So for all the hype about raising taxes, it would only happen for a small minority of Americans.

The bite on top earners won't be that painful. Some families will feel squeezed if the tax hikes go through, like those whose incomes are just over the threshold--especially if they live in expensive coastal cities and have kids in college. But most high-income taxpayers would fork over a relatively small portion of their incomes in additional taxes. A two-earner family with two kids at home and $500,000 in annual income, for example, would pay about $13,000 more in taxes under Obama's plan. (Use this tax calculator to run your own before-and-after scenarios.) That's an extra 2.6 percent of their income, not counting financial-planning changes that could lower the family's tax burden.

That extra tax isn't a trivial amount. But since the wealthy save a much higher portion of their income, it's not likely to affect the family's standard of living that much, or translate into deep cuts in overall consumer spending that would threaten an economic recovery. The wealthy obviously spend much more per person than everybody else, but compared with the huge middle class, there aren't that many rich shoppers. Spending by middle- and low-income earners is what drives the economy. By leaving their taxes alone, the Obama proposals would at least ring-fence the incomes of those who do most of the nation's spending.

From Ezra Klein at www.washingtonpost(dot)com, a graphic about the differences between the Bush tax cuts and the Obama tax cuts(subject to change, of course):