Time capsules are embarrassing in their self-consciousness – those overcareful caches of objects intended to evoke respect, wonder and nostalgia in some imagined future audience. It is only slightly better when they are buried on Earth, rather than blasted into space in case an alien life form finds them and is inclined to leaf through the mementos.

The capsule chosen for the G8 summit in Japan, which included a list of the hotel staff and police who took part and will be buried inside a monument representing drift ice as a symbol of global warming, has the myopia and grandiosity typical of the genre. There is also a sweetness about the commemoration, which the G8 summit shares.

It is easy to knock the G8. Many did so as the summit ended yesterday, saying that the most powerful countries in the world had failed to solve anything. Yet looking at the images of the leaders together and hearing the statements from the margins of the meeting – after two leaders had met on their own – it is hard to dismiss its value. It is a rare chance for those leaders to talk to each other without the expectations that rest on a visit of one to another.

One problem is that the expectations have become high and precise. The G8 (which consists of Britain, the US, Canada, France, Germany, Italy, Japan and Russia) has ducked the one question it might be expected to answer, however – whether it is a club for the most-powerful democracies, in which case it should leave out Russia, or whether it is for powerful countries of any stripe, in which case it should bring in China.

The scorn was rising even before the summit closed. Environmental campaigners criticised the leaders for their “shared vision” on curbing carbon emissions – G8 countries emit about 40 per cent of the world total. They are right. The vision lacks firm numbers and even though it reaffirmed the aim of cutting emissions in half by 2050 it was not a commitment, nor was there agreement on targets along the way. If this is a failure it is not a new one. Nor is the G8, by definition not including China and India, in a position to ease the deadlock with the developing world giants on whether they will join in.

The drive by the US and Britain to win support for sanctions against Zimbabwe also looked inconclusive. The statement of support for Afghanistan was not new, although it came with a reminder that the G8 wanted elections and urged the country to do more for its own security. On the subjects of high food and oil prices, the leaders expressed distress but said nothing that had not been said already about those urgent problems.

The real value lies in the small shifts of tone and the small decisions, such as Russia’s intention to keep talking about the proposed US missile shield in Eastern Europe, although it loathes the idea; and the decision by the European Union to send its representative back to Iran for more talks. Those moves can go a long way to prevent disputes from escalating. For all the lack of grand bargains – always beyond the reach of the G8 – there were enough small measures to justify a time capsule.

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