NATO, the North Atlantic Treaty Organization, is a remarkable case of institutional survival in the face of changing circumstances. It was created in 1949 to protect western Europe from the Soviet threat, and in 1989 the Soviet threat vanished. Yet NATO not only survived the collapse of the Soviet Union but expanded, taking in all the former satellite states of eastern Europe and even the Baltic republics that had been part of the Russian empire for more than 200 years.

But the Georgian debacle could break NATO.

In those eastern European countries that were so recently ruled from Moscow, the presence of Russian troops in Georgia has reawakened all the old fears. Last Thursday, Poland hastily agreed to let the United States place anti-ballistic missile sites on its soil, on condition there must also be a full-fledged U.S. military base in the country. Why? Because then, if Russia attacked Poland, the United States would automatically become involved.

The rhetoric in the new NATO members has been almost as hysterical as that in Georgia itself, where President Mikhail Saakashvili has been calling the Russians "21st-century barbarians" who "despise everything new, everything modern, everything European, everything civilized."

Similar rhetoric pervades the parallel universe of the U.S. media, where the fact it was Georgia that started this war by unleashing a merciless artillery barrage on South Ossetia and then invading it has been virtually erased from the storyline.

It's a rousing morality tale that hits all the right notes for an American sensibility, and it's not just Georgia's PR firms that are pushing this line. It's also the U.S. State Department and the Pentagon, which had been building Georgia up as a key U.S. ally on Russia's southern flank.

Yet U.S. Secretary of State Condoleezza Rice looked deeply uncomfortable Friday in Tbilisi as she stood beside the ranting Saakashvili.

Perhaps she was pondering the fact that, while the "new Europe" of former Soviet-bloc countries uncritically backs Georgia and the U.S. commitment there, the "old Europe" of Germany, France, Italy and their neighbours mostly does not.

This is a problem if she wishes to pursue her goal of bringing Georgia and Ukraine into NATO, since "old Europe" is the core of NATO, with three times the population and five times the wealth of "new Europe."

Angela Merkel, the German chancellor, put it quite carefully after she met Russian President Dmitry Medvedev Friday: "Some of Russia's actions were disproportionate, (but) it is rare that all the blame is on one side. In fact, both sides are probably to blame. That is very important to understand."

The Italian government warned against trying to build an "anti-Moscow coalition." French Foreign Minister Bernard Kouchner works for the most pro-American French leader in recent history, President Nicolas Sarkozy, but he still said: "Don't ask us who's good and who's bad here. We shouldn't make any moral judgments on this war."

This will all be seen as "appeasement" by the neo-conservatives who still rule the roost in Washington, but many in western Europe would call it common sense.

The Russians will stay in Georgia until they have dismantled the Georgian army and navy bases that could threaten the ethnic enclaves of South Ossetia and Abkhasia again, removing all the new American weaponry that gave Georgia an offensive military capability, and then they will withdraw to the enclaves as the ceasefire agreement requires.

Sarkozy brokered that ceasefire, and agreed to write those clauses into it.

He knew they allowed Russian forces to stay on Georgian territory until the military threat had been nullified, and he accepted them.

He did so because he did not really see Russia as an aggressor in this crisis (although he will not contradict the United States publicly by saying it in so many words).

But, if the United States pursues its goal of bringing Georgia and Ukraine into NATO, there are only three options.

If "old Europe" digs in its heels and refuses, on the grounds it does not need Russia as an enemy, then either the United States drops its demand or NATO breaks up.

The third alternative (and perhaps the likeliest) is that "old Europe" agrees to let the two former Soviet republics join -- but with the unspoken reservation they will never actually go to war with Russia to protect them.

That would be a less dramatic end for NATO, but it would be an end. A two-tier alliance is no alliance at all.

Gwynne Dyer is a London-based independent journalist whose articles are published in 45 countries.