The conflict between Georgia and Russia would have exploded anyway, in some form, were Nato to have pressed ahead with offering Georgia a start on the road to membership, possibly at its meeting at the end of the year. The eruption on Friday should not deter Nato from taking that step soon.

Of course, many Nato members will consider how, had Georgia already been a member, they would have had to defend it. Germany will win more support for its argument, which dominated the Nato summit in April, that it would be wrong to offer membership for fear of provoking Russia and while its territory remains in dispute. Alarm at this near-war on Europe’s borders will easily persuade more governments of the need for caution.

That would be wrong. It would tell Russia that it had an effective veto over who joined Nato. It would discourage the pro-American and pro-European spirit of President Saakashvili, elected in 2004 partly for those sentiments. It might even make it harder to agree the deployment of international peacemakers in South Ossetia by showing that the US and Europe were indifferent to Georgia’s case.

There appear to have been serious miscalculations, more so on the Georgian side. Given the close contact with the US, that might be extended to the US as well. Saakashvili may have deluded himself that four years of US help in equipping his armed forces enabled them to make a dash for their prize. In taking advantage of the distraction of the Olympics, he looks sneaky, and so jeopardises his claim to the moral high ground.

But Russia, in the drama of its move inside internationally recognised Georgian sovereign borders, has escalated the dispute to a level that demands a formal response. At the very least it has sacrificed prospects for the defence pact with Europe that it has mooted.

The Nato summit was a clash of philosophies about Europe’s future. On one side was President Bush, making one of his best speeches, about the value of bringing Georgia and Ukraine into Nato as an assertion of common principles. On the other was Angela Merkel, the German Chancellor, laying out why this should be postponed, perhaps for ever, even at the cost of undermining the pro-Western camp in Georgia. (British officials let it be known that they were on the American side in sympathy, but as the US would not win, they were “on the side of compromise”.)

Merkel won. But one important concession was made: the promise of membership at some point. Of course, the clash makes it important that the South Ossetia question begins to be resolved, by exploring the offers of autonomy made by Saakashvili and whether a force with an international mandate might replace the Russian force that has lost any claim to be neutral. But there are precedents (Turkey and Greece) for including members within Nato who have unresolved territorial questions.

One of the uses of Nato is to draw a line between countries that share principles and those that do not. Georgia has indicated which side it is on. That is worth rewarding. It would be giving in to Russian bullying to believe that the cost of membership is a war.

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