It’s the easiest thing in the world to mock this weekend’s economic summit in Washington, unhelpfully entitled Bretton Woods II. Many have, and it doesn’t start until today. That would be wrong.

It’s the right group of countries – the G20, which includes the main developing countries and the industrialised world, bringing in Saudi Arabia and Russia, as well as India and China. This is the first time the group has brought together heads of government, rather than finance ministers and central bank governors, raising a dowdy technical forum to something more weighty. It’s the right moment, after the first crisis of collapsing banks has passed, but while financial stability and recession still need urgent attention. And it’s a point when it is important for these governments to defend the principles of capitalism and free markets, the only respect in which this gathering really echoes its famous namesake.

Sure, there is the awkwardness that it takes place in the last days of George Bush’s presidency. Barack Obama does not want to attend, to respect the principle that there is only one president at a time, although the hyper-visibility of his transition team, and the silence, even absence, of the Bush people lends a sense of unreality to this propriety. So commitments will have to be run past Obama advisers offstage. But that doesn’t make them meaningless, whereas to have waited two months until Obama was in the White House would have missed the moment.

It’s asking for trouble to take one of modern history’s most resonant names and then put a II after it. To compare this year’s financial turmoil, and “is-it, isn’t-it” recession to the last year of the Second World World would be grotesque.

Nor does the world have the simplicity that it did when 44 allied countries gathered in July 1944 at Bretton Woods, New Hampshire, to agree the rules for commercial and financial dealing with each other. The creation of the International Monetary Fund and the World Bank (then, the International Bank for Reconstruction and Development), and the agreement on monetary policy and management of exchange rates – there is nothing in this weekend’s summit to compare. Nor should there be. The size and complexity of financial markets make much of Bretton Woods look anachronistically tidy (as they had done, indeed, by 1971, when the currency exchange system collapsed). Power is no longer concentrated in the hands of a few countries. This year’s crisis has helped the IMF to rediscover a role, but that was previously in doubt, as fewer countries needed its help and its standard prescriptions for reform were challenged by half a century of development experience.

But there are still valuable plans this weekend. One is for Gulf states and China to inject more cash into the IMF. There is agreement to put less weight on credit ratings agencies’ findings. The crisis has exposed their conflicts of interest as they compete to win the business of the banks they rate, as well as the limitations of their analysts, paid far less than the financiers they are trying to analyse.

There will be a nod towards cooperation between financial regulators, which is useful, although with the British-Icelandic tussle in mind, it is not clear whether this would triumph where national interests diverge. There will be thoughts on regulation of hedge funds, and perhaps on tax havens. And there may be (Gordon Brown is keen on this) an expression of desire to salvage the Doha trade round. Many may say that this is meaningless, as the US, India and the European Union have clashed so bitterly on farming. Yet one great concern about Obama’s presidency is whether he gives in to a protectionist Congress. A statement committing the US to the opposite principle is valuable.

Like any sequel, this summit is a magnet for would-be stars who want to hitch their reputations to past success. But the only big mistake it has made is in its choice of its own name. That aside, the day-and-a-half in Washington is worth something.

Times Recommends

• We have kit and leadership. Let’s go
• Behind the scenes at the biggest deal
• Conferences — what a waste of money