If it weren’t for Katrina, the federal estate tax might be on death row today, set to expire – permanently, this time – in 2010.

But now the case for killing this tax is weakening. And that creates a planning dilemma for many people who don’t think they’re the ones the tax was meant for – the rich.

The wide-ranging Bush tax cuts of 2001 included a gradual reduction in the estate tax over the years, eliminating it entirely for people who die in 2010. But to get Democrats’ votes, Republicans agreed to let the previous tax rules come back in 2011.

Republicans have pushed to make the 2001 cuts permanent, and Senate Majority Leader Bill Frist had scheduled a vote on the estate tax for last week. (The House approved a similar measure in April.)

Then Katrina hit. With Americans glued to images of poor people struggling in New Orleans, it just wasn’t the time to approve a tax cut that would mainly benefit the wealthy. Early last week, Frist postponed the vote, which is now likely this fall.

But should the estate tax be repealed?

In 2001, that did seem to make sense. Polls showed Americans thought the tax was unfair, even though most people never had to face it. Back then, it applied only to portions of an estate above $675,000, and that was to go to $1 million in 2002. Nationally, only about 2 percent of estates were big enough to pay the tax.

But an estate isn’t just cash and investments. It includes one’s home, assets in a retirement plan such as a 401(k) and any life insurance benefit left for heirs. In the high-cost, high-income areas on the East and West coasts, lots of essentially middle-class people would leave estates worth more than $1 million.

And, of course, the federal government had been running enormous budget surpluses. Killing the estate tax was a popular idea and seemed pretty painless in 2001.

But now we’re running huge deficits, and Katrina has drawn attention to the growing population of poor people who need government services.

Complete repeal of the estate tax would reduce federal revenues by $290 billion during the first five years, according to one of Congress’s most conservative estimates.

Unless Washington finds a way to cut spending dramatically – and that’s hard to imagine – more money’s got to come from somewhere, and the well off are the logical source. After all, they have enjoyed the lion’s share of the other tax cuts as well, such as those on income, capital gains and dividends.

Proponents of estate-tax repeal have scant evidence to support their claim that the tax forces substantial numbers of heirs to sell small businesses and family farms. Smart business people set money aside to pay the tax, or they buy life insurance.

This year, estates worth up to $1.5 million are exempt from the estate tax, and that is set to rise to $2 million next year and $3.5 million in 2009. Is this the time to worry about people with that much?

Clearly, the Democrats who oppose estate-tax repeal are in a stronger position than they were just a few weeks ago. For the moment, the problems of the poor are center-stage.

Many Democrats support compromise, and there have been moves to create a permanent exemption of somewhere around $3.5 million. The tax would thus apply only to those most of us would consider truly rich.

But no one knows what will happen. For the moment, it’s prudent to assume the pre-Bush-cut rules will return in 2011 – with the tax triggered at $1 million.

If you expect to be around until then and to have more than that to leave behind, best prepare a source of funds to pay the tax. Buy a life insurance policy or plan to leave enough liquid assets to cover the bill. Under the old law, the tax took as much as 55 percent of the taxable portion of the estate.