Uncle Hubert was upset. “They're going to bump me off,” he announced, halfway through dinner. “They're going to push me under a train, or put arsenic in my wine. And why shouldn't they? This is the best opportunity they're ever going to get.” I should probably explain that Uncle Hubert isn't my uncle.

He's my wife's uncle (is there such a thing as an uncle-in-law?). He lives in New York, but was visiting LA to attend a shipping conference.

It would be fair to say that Uncle Hubert has done very well out of the shipping business: well enough, at least, to be losing sleep over America's bizarre and controversial “estate tax” - known as either the “death tax” or the “Paris Hilton tax” depending on whether you're a right-wing radio talk show host or Barack Obama.

I say bizarre because this 45 per cent tax, levied against estates worth more than $2 million, will be repealed in 2010 - when President Bush's tax-cutting legislation expires - only to be reintroduced precisely one year later with the exemption halved to $1 million and the rate increased to 55 per cent. In other words, if your parents are rich and alive, 2010 would be an excellent time to consider double murder. Indeed, your accountant might recommend it.

Of course, Uncle Hubert doesn't seriously think his life is at risk from my wife's cousins. But I can understand why he's concerned. Ten years ago, having a $1 million estate made you rich. These days, having a $1 million estate means you bought a house before the property bubble. In California, for example, it is estimated that there are now almost 500,000 “millionaire households”. No wonder Obama - who opposes a permanent repeal of the estate tax, on the ground that it would benefit Hilton - lost the Democratic primary election here.

Then again, there are plenty of Americans who think that the likes of Uncle Hubert should shut up and hand over their wallets: Americans such as William H. Gates III, for example, whose $58 billion estate will be a mere $57,999,000,000 over the 2011 estate tax exemption, meaning that his children will be liable for a theoretical $31,899,450,000 tax bill, which will have to be paid in cash, as is always the case with the federal government. The Bill is theoretical because Gates, who argues that repealing the tax would discourage philanthropy while forcing the Government to raise other taxes, is trying extremely hard to give away his fortune before he ascends to the Great Control Panel in the Sky.

Which is all very well. But given the $31.8 billion at stake, I would advise Mr Gates to join Uncle Hubert and all those other American millionaires and billionaires in taking a long holiday in 2010. And by long, I mean a year long - or at least until the future of the estate tax is certain. This isn't to say that the offspring of America's wealthy can't be trusted, of course. It's just that, well... it might not be a bad idea to spare them from the temptation, regardless.

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