The following editorial with the above title appeared in the Guardian this morning:

"We don't pay taxes. Only the little people pay taxes," the American billionaire Leona Helmsley is meant to have said. Tax evasion earned her a prison sentence and pariah status. So why do world leaders tolerate those international equivalents of Leona Helmsley, the tax havens? As they meet in Doha this weekend, heads of state have an excellent opportunity to launch a crackdown on the havens. Sadly, they are unlikely to take it.

Havens are the 70 or so territories that serve as the boltholes of tax avoiders, who enjoy low tax rates and no questions asked. Companies who set up shop (or shopfront, since hardly any real business is done) in these places duck their financial obligations to their host societies. Tax havens thus rob poor countries of vital income. They also nurture the shadow banking system, that web of shoddy deals and bad faith which grew so quickly during this decade's boom in obscure financial instruments. If good business practice is defined by openness, accountability and social responsibility, tax havens are in the opposite corner. Barack Obama certainly thinks so. The French and Germans agree, while Alistair Darling is looking into the issue.

But even as the various heads of state and ministers gather this weekend, few expect any breakthrough on the issue. For one thing, the delegate list for the UN summit looks fairly underpowered. Of major European leaders, only Nicolas Sarkozy is set to attend. Campaigners on the ground report that the heads of both the World Bank and the International Monetary Fund are going to give it a miss. The summit's entire purpose is to discuss how to channel more money into development - yet delegates are unlikely to act on the evidence from Christian Aid that tax avoidance costs poor countries around $160bn a year, dwarfing the $100bn they get in aid.

But if tax avoidance is ever to be tackled, it will have to be done globally. Otherwise, companies will treat the various bilateral agreements as so many hurdles to be jumped over. Instead, the UN's tax committee should be upgraded. Tax is not just a matter for officials, which is how the UN treats it at the moment, it is also one for governments - and tax policy must be discussed in as open a forum as possible. And the principles international tax law should embody are equally to do with openness: multinationals should report their profits and tax paid in each territory they operate in, and havens must cooperate with international tax authorities so that we all know who is paying how much tax to whom. Politicians often bandy about words such as transparency and accountability; they should put them into practice.

I agree.

This is the time for action.

For all the protestations of the havens on this site and elsewhere, for all the 'off the record' briefing by the Big 4 who are so ashamed of their tax haven operations they will not speak about them, for all the inactivity of the International Accounting Standards Board on country by country reporting, the truth is becoming apparent: nothing but radical reform of these places will do.

Five years ago an editorial like that above was unimaginable. There was no Tax Justice Network.

We don't claim all the credit: I am pretty sure Christian Aid had a lot to do with this editorial. But it's been very good to be part of the process of change.

We aren't at the tipping point yet, although the current mood of the OECD is welcome indication that we are on our way. And I think it will happen. And the pace of change is extraordinarily rapid. Not fast enough to hold our breath. But good, none the less.

That's why we have to keep up the pressure now.