As President Saakashvili looked up in terror at the Russian helicopter roaring over the besieged town of Gori, with his troops in retreat and Western allies offering no more than words against Moscow, the catastrophic consequences of his decision to take military action in South Ossetia last week could not have been clearer.

In his attempts to clamp down on pro-Russian South Ossetian separatists, Mr Saakashvili appears to have made one fundamental, disastrous miscalculation: that the Bush Administration and the West viewed their relationship with Georgia as more important than that with Russia.

Last night President Bush issued a strong condemnation of Russia’s actions, but did not refer to any action that the United States might take in Georgia’s defence. Mr Bush said there was evidence that Russia was trying to overthrow a democratically elected government and planning to attack the civilian airport in Tbilisi. “Such an action is unacceptable in the 21st century,” he added.

A few hours before Mr Bush’s strong but not very supportive words, a flak-jacketed Mr Saakashvili had visited Gori, about 40 miles north of the Georgian capital Tbilisi. As a helicopter appeared, his bodyguards pushed him to the ground, and then into a black armoured vehicle, shouting “Go, go, go!”. His US-trained army was soon fleeing the town in disarray.

By last night Alexander Lomaia, the secretary of the Georgian Security Council, declared that Russian forces had occupied Gori. “This is a total onslaught,” he said.

Mr Saakashvili, the flamboyant, multilingual, Harvard-educated law graduate who swept to power in the 2003 bloodless Rose Revolution, has particularly close ties to the neoconservative, pro-democracy wing of the US Government. Mr Bush had repeatedly championed Georgia as a bastion of democracy.

Only four months ago Mr Saakashvili, 40, hailed a breakthrough in his campaign to turn his poverty-stricken country into a free-market member of the West after Nato leaders declared that Georgia would one day join the military alliance. He had sent 2,000 troops to Iraq and harboured serious hopes of joining the European Union.

He was the embodiment, in Western eyes, of how the newly emerging Eastern Europe should look: young, free-market, dynamic and a buttress against the expansionist aims of an increasingly powerful Russia.

Now he risks losing not only those hopes but also South Ossetia and his grip on power itself, with Moscow’s intention of seeing him overthrown becoming clearer by the day. Zalmay Khalilzad, the US Ambassador to the United Nations, accused the Kremlin of seeking Mr Saakashvili’s downfall. He said that Sergei Lavrov, the Russian Foreign Minister, had told Condoleezza Rice, the US Secretary of State, that “the democratically elected President of Georgia must go”.

Analysts believe that Russia has been waiting for an excuse to invade Georgia and destroy Mr Saakashvili, and the Georgian President’s decision last week to clamp down on separatists in South Ossetia appears to have been the disastrous misjudgment that gave Russia an opening. The belief in Washington is that Vladimir Putin, the Russian Prime Minister, thought that the West would do little to help Georgia because of Russia’s strategic might and because much of Europe depended heavily on its gas supplies.

The most support that Georgia received from Western allies yesterday was a ceasefire call from the G7 group of nations and an offer to broker a ceasefire from the European Union, both brushed aside by Moscow.

Gordon Brown said that Russia was damaging its international reputation, while David Cameron, the Conservative leader, labelled Russia a “dangerous and massive bully” and called for Georgia to be given accelerated Nato membership. Mr Brown said: “There is no justification for continued Russian military action in Georgia, which threatens the stability of the entire region and risks a humanitarian catastrophe.”

Bruce Jackson, an influential advocate of democracy in Eastern European, said that the Russian invasion smacked of “rank premeditation”, adding: “The Georgians were naive to think that the international system could protect them. There will be a lot of blame to go around for this. We have failed a young democracy.”

Defeat in South Ossetia is a bitter blow to Mr Saakashvili, who came to power championing a united Georgia. His political currency has been debased at home because his Western allies — particularly the US — appear to be doing little to halt the deaths of thousands of Georgian civilians. The wisdom of his gamble will inevitably be questioned by his own voters, as will his staunchly pro-Western policies.

Even before the war, Mr Saakashvili was facing growing domestic unrest amid accusations that he was trying to consolidate power. Tens of thousands of people attended a protest rally in May, challenging the results of a snap presidential election in January.

Roman Kuzniar, Professor of Political Science at Warsaw University, said: “The Georgians made a big mistake. Now Georgia will have to take the toll, most probably disproportionately severe.”

Bruce George, a Labour MP and close follower of Georgian-Russian relations, said: “I believe the Georgians were suckered into this and paid a very heavy price. If you embark on a war, as the Georgians did, you have to work out what the consequences will be. It was inevitable that the Russians would react very heavily.”

Under Mr Saakashvili, Georgia has achieved impressive economic growth and attracted foreign capital. The war is likely to damage the Georgian economy significantly and scare off many foreign investors. If Georgia had been a Nato member, it could have invoked the alliance’s Article V mutual defence clause, requiring nations to come to the assistance of an ally under attack.

The Russian aggression, therefore, has greatly complicated Georgian hopes of Nato membership. David Lubin, an economist at Citigroup, said: “This makes Nato expansion much less likely. The last thing the United States needs now is another front. That’s exactly what Russia is taking advantage of.”

Franco Frattini, the Italian Foreign Minister, said: “This war has pushed Georgia farther away not just from Europe, but also complicates the Nato council in December.”

The case for and against Nato membership

For Nato is a political as well as a security organisation and the objective of its expansionist policy is to seek to embrace into the same network as many countries in the wider European family as possible. With the entry of Estonia, Lithuania and Latvia into the alliance, the pro-Western state of Georgia felt that it had every right to join the queue of applicants. The alliance has agreed to admit it in principle because membership helps to spread democracy and stability. Extending membership would protect a strategic Western ally from the threat of Russian attack

Against Nato’s expansion programme has caused deep anxiety in Russia. The proposed installation of elements of America’s missile defence system in Poland and the Czech Republic is viewed with suspicion, and inviting Georgia to join the alliance is seen, from Moscow’s viewpoint, as another stab in the back. The Caucasus is Russia’s unstable backyard. Nato has no interest in provoking Russia for the sake of adding another country to the long list of members. Relations with Moscow would be seriously damaged. The West could be drawn into a new Cold War or, worse, open conflict with the Kremlin

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