One of the talents of the Conservative Party since the days of Margaret Thatcher has been to explain economics as if the country is a household, so everyone can understand ideas such as the need to cut spending when you're in debt. So I imagine they'll use the same homely reasoning to explain their support for a new royal yacht. Because anyone who's run a household knows, when money is tight and you've spent two years insisting your family can't have anything, if you're prudent that's when you buy a 650ft yacht with a theatre and a helipad.

That's why, if debts become a serious problem and it feels there's no escape from the bailiffs' letters, you should consult a registered financial adviser, who will explain how to manage the situation by buying a royal yacht for £80m with a space to seat two royal buses.

Because even in times of austerity we have to be prepared to spend SOME money. And most people, if asked for their feelings about the current restraint, will say, "I understand the need to close the library and the local A&E department. And, while the rise in tuition fees will bankrupt me, I accept it's a necessary measure. But I can't bear the thought that if the Royal Family fancy going on a yacht, they have to hire one because they don't have one of their own", and break down sobbing.

The Daily Mail, which campaigns for this yacht, says "it won't cost you a penny" as it "will be run by a charitable trust", and claims that "we have been touched by generous and unsolicited donations from readers". That's understandable, because if there's one cause that deserves our charity, it's this one. I expect readers from Haiti are enclosing cheques, with a note saying, "Since the earthquake, my family has been living in a sewage pipe but when we saw you had to hold a banquet for the King of Morocco in a palace without the option of bobbling about on a yacht, it put my trifles into perspective."

One minister suggested the yacht would be "an ideal way to thank the Queen for all she's done for this country over 60 years". And certainly it's about time her efforts received a little financial reward. All these years, she's queened away for nothing in return. It's one of the great unsung jobs being Queen, toiling away in the background with barely a moment's recognition.

The yacht will also be used for "training for young people" and "scientific research facilities". You might suggest another way to fund training for young people and scientific research would be to fund training centres, and scientific research. But it's more productive to buy a royal yacht and let selected teenagers and scientists on it for three days a year when it's not being used to entertain Saudi arms dealers. So it would be wrong to sneer. As someone wrote to me yesterday, "monarchists should be allowed their yacht, as long as Republicans get to pick the captain".