As you read this, another corner of Europe has been ethnically cleansed. That means young men murdered, old women driven out of their lifelong homes, villages plundered and torched. As in Bosnia, so now in South Ossetia, with the butcher's work largely done by irregular militias. "We did carry out cleaning operations, yes," the militia leader "Captain Elrus" told the Guardian's Luke Harding. These violent crimes have been committed under the noses of Russian troops, now unilaterally rebranded peacekeepers by the simple expedient of being given blue helmets. This ethnic cleansing has extended to the buffer zone around South Ossetia that Russia has unilaterally established, exploiting an alleged loophole in the ceasefire agreement brokered by Nicolas Sarkozy on behalf of the European Union.
These facts, established on the ground by brave and careful reporters, are the true human measure of Europe's failure to keep its cardinal promise of peace even in its own backyard. They are also the measure of Russia's deliberate, strategic challenge to the whole late-20th century way of doing politics and international relations that the EU represents. Do not underestimate the significance of this moment.
Two things must be said, which complicate but do not negate the point. First, Georgia's leaders behaved with reprehensible folly in escalating the conflict in South Ossetia on August 7, allowing their forces to kill and wound civilians, and failing to anticipate the hammer blow of Russia's military reaction - despite indications that it had been rehearsed. "We did not prepare for this kind of eventuality," confessed Batu Kutelia, the Georgian deputy defence minister. What irresponsible idiots.
Second, the dying Bush administration behaved with characteristic incompetence in allowing the Georgian government to nurse even the shadow of a hope that the US cavalry might ride to the aid of this would-be Israel of the Caucasus. Warnings to the contrary were reportedly conveyed by the state department, but not with equal clarity from all parts of this dysfunctional administration. Worldwide ridicule of Washington's indignant response also demonstrated how much credibility the US has lost due to the invasion of Iraq. (Don't invade a sovereign country - that's what we do.)
So, yes, there was fault in Tbilisi and Washington. But finding fault with the US (a sport at which Europeans excel) and Georgia (a faraway country of which most Europeans know nothing) reduces by not one jot or tittle the challenge Russia now poses to the whole way western Europe has tried to conduct human affairs since 1945 - and the creed most of Europe has lived by since 1989.
"Territorial integrity" is not the heart of the matter here. The essence of our new European way of doing things is something more like procedural integrity. The frontiers of existing states must be respected, but in exceptional cases territories within states may negotiate special autonomies or even vote to become independent, like Slovakia and Kosovo, or perhaps Scotland one day - but always by peaceful means, by negotiation and consent, with the sanction of national and international law. The how matters even more than the what.
That's our fundamental claim, which Putin's Russia now challenges head on. Its message is that the unilateral use of force in the advancement of national interests is part of what great powers do; that the EU's postmodern, multilateral, law-based order is a transient 20th-century anachronism; and that, in the words of Thucydides's Melian dialogue, "the strong do what they can, and the weak submit".
So what is Europe's answer? The outcome of Monday's EU emergency summit was less bad than it might have been. By contrast with the last emergency summit, held five years ago over Iraq, a minimal unity was preserved. But the measures agreed were still weak. "Thank God common sense triumphed," commented an apparently satisfied Vladimir Putin. And the unity itself is weak, reflecting differing levels of energy dependency on, and diverse historical experiences with, Russia. Moscow will do everything in its power to exploit these differences. Monday's Izvestia had a fascinating coloured map of EU states divided into four categories, with Britain and Poland tagged "virulent critics", while Germany, France, Belgium and Italy received the complimentary label of "Moscow's lobbyists".
I found the tone of mild self-congratulation from Sarkozy and José Manuel Barroso at the post-summit press conference in Brussels inappropriate. You should not allow that tone to creep in when, even as you speak, poor women and children are being made destitute, if not worse, partly as a result of Europe's failure. A defeat is not a victory. And this summit can only be counted a success if it begins a fundamental rethinking of Europe's whole policy towards Russia.
What we need is a twin-track approach, combining elements of muscular deterrence and skilful engagement - if you will, of cold war and detente. Putin's is not the only view in Russia. Hopes that President Medvedev's would soon be audibly different have receded, but there are others, including the private views of some worried Russian capitalists. It must remain clear that the door is still open to the kind of strategic partnership the west dreamed of in the 1990s, with Russia as a new pillar of liberal international order.
Our new working assumption, however, must be that it will for the foreseeable future remain Putin's Russia: a ruthless great power, determined to roll back the influence of the west and establish its own 19th-century style sphere of influence in the post-Soviet space; and one prepared to use violence, intimidation and extortion to realise its national interests, which it defines as extending to the "protection" of millions of Russians in other sovereign states around its borders - in Crimea, for example, a part of the sovereign state of Ukraine where slightly more than half the population identify themselves as Russians and the Kremlin has its Black Sea fleet harboured at Sevastopol.
Yalta, c'est fini, declared Sarkozy at the Brussels press conference, alluding to the alleged division of Europe into two spheres of influence at the 1945 Yalta conference. But a new kind of Yalta may be beginning - at that very same town in Crimea, and many like it, where Mother Russia yearns to look after her own. Europe must do what it can for Georgia, including a visible presence on the ground. But strategically even more important is to do what it can for Ukraine, a large and pivotal state that (unlike Georgia) still more or less controls all the territory within its borders.
David Miliband was absolutely right to go there in response to the Georgian crisis. The EU should now give Ukraine a clear perspective of membership. It should put monitors, officials, lawyers, police advisers and development workers - Ukrainian and Russian-speaking - on the ground, especially in regions such as Crimea. Our response should be realistic in assessing not just Russia, but our strengths and weaknesses. Russia does tanks. Europe is not good at doing stuff with tanks. But we do a thousand other things, each smaller, softer and slower than a tank, which, given time and the perspective of eventual membership, can be a force more powerful. This European model is now on trial.
Timothy Garton Ash