One way or another all New Zealanders will help pay for the reconstruction of Christchurch. Most of them will want to help pay in some way, whether through a levy on incomes or the inevitable rise in household insurance premiums, or both. A developed nation expects to pay. Not many New Zealanders will have expected their Government to issue an international appeal for funds.

Practical aid is one thing - the search and rescue task after a disaster of this scale is beyond a small country's resources and New Zealand's 150 trained searchers have been augmented by 429 from other countries - but an appeal for cash underlines the scale of the task still ahead.

The Prime Minister is prepared to promote the appeal on United States television if he can get a date with the likes of David Letterman or Oprah Winfrey. His previous chat with Letterman for the sake of tourism did not do much for the dignity of his office but on this subject hopefully he would not face the same risk. He notes that an international appeal by Australia raised A$389 million ($527 million) for bushfire relief. If our richer neighbour is prepared to put its hand out in these circumstances, why should we hesitate? Half a billion dollars is not a trifling sum.

Treasury advised the Cabinet yesterday that the bill for Christchurch's two earthquakes could reach $20 billion. It appears not quite half of that can be met from the country's public insurance arrangements and a further $5 billion from private insurance. That leaves perhaps $6 billion to be found from additional taxation or Budget savings or both.

To put that figure in perspective, the Government is spending over $70 billion this year, $8.6 billion more than it is receiving in taxation and other revenue. It was planning to keep $1.12 billion aside for discretionary spending and $1.39 billion for unexpected capital needs in this year's Budget. Christchurch will require all of that and perhaps $3 billion more.

At the same time, the loss of output from half of Christchurch will deplete total tax revenue and add to welfare outlays. Emergency payments have topped $3 million so far and the relief announced yesterday to carry business employees through the next six weeks is expected to cost up to $120 million.

The earthquake will be a setback to the recovery of the public accounts, delaying the return of a Budget surplus and adding to the public debt. The city's reconstruction will pull public and private investment into domestic activity rather than the export developments the Government wants to encourage.

But it is a cost this economy will have to meet. An international disaster relief appeal will raise at best a fraction of it. The value of an international appeal is in the giving as much as the receiving.

Human nature has an urge to help whenever scenes such as those in Christchurch are transmitted around the world. Many, especially New Zealanders living overseas, feel the same impulse that drives those here who welcome the idea of a special tax levy for Christchurch.

Numerous avenues for private donations have been set up already. The Red Cross, the Salvation Army and trading banks have set up online methods of contributing. Lotto will give half of its takings this week to the Government's fund. An international appeal is just one more channel for charity.

It is an unfamiliar one for this country. We are not accustomed to asking for help or to receiving it. But we should do so gracefully. Disaster summons the best instincts in people near and far. Sympathy and generosity will bind us long after the emergency lasts. The world has watched Christchurch suffer and the response of people the world over may be worth more than money can measure.