Why China and Russia rebuffed the West on Syria
The double veto by China and Russia of a UN Security Council resolution condemning the crackdown in Syria represents a serious blow to efforts to reach international consensus on how to grapple with President Bashar al-Assad's regime.
It also signals a much tougher stance from Beijing and Moscow who are clearly not happy to see the weight of the Security Council ranged against the Syrian authorities.
Western diplomats argue that the wording of the resolution - which was proposed by Britain, France, Germany and Portugal, in co-operation with Washington - was carefully drafted to try to take account of Chinese and Russian concerns.
The fact that these efforts failed in such a dramatic manner represents a clear diplomatic rebuff to the West.Libya
It only heightens divisions on the Security Council, where Brazil, India, South Africa and Lebanon abstained, suggesting that the new era of intrusive diplomacy ushered in by the UN Security Council resolution 1973 on Libya last March looks set to be short-lived.
Libya is perhaps the prime reason behind the Chinese and Russian vetoes. Beijing and Moscow both abstained in the March vote, thus allowing the resolution to go through.
Security Council vote on Syria
In favour - Bosnia and Hercegovina, Colombia, France, Gabon, Germany, Nigeria, Portugal, UK, US
Against - China, Russia
Abstained - India, South Africa, Brazil, Lebanon
It opened the way to the Nato air campaign - ostensibly to protect civilians, but in practice one of the key factors in the demise of Col Muammar Gaddafi's regime.
Both the Chinese and Russian governments seem to think that the West took advantage of this resolution to intervene militarily in a Libyan civil war. They are determined not to allow any similar resolution to go forward, hence the double veto.
Arguments that this Syria resolution was worded very differently and would not have prompted military action of any kind fell on deaf ears.
Russia's UN ambassador Vitaly Churkin insisted that the proposed resolution was all about regime change in Syria.National sovereignty
To be fair, many Western governments have made little secret of their desire to see President Assad gone. But they are well aware that the Libya "template" cannot be applied to Syria.
There are other reasons, though, that explain the double veto - not least the "traditional" Russian and Chinese concerns about resolutions that seek to intervene in the internal affairs of a country.
In this sense Russia and China are staunch defenders of old-fashioned national sovereignty - perhaps fearful of resolutions one day being directed against them.
Then there is immediate national interest. For both Beijing and Moscow, Libya was essentially a marginal player in the region. But Syria, especially for the Russians, is a very different matter.
The Syria of the Assad dynasty has been - and remains - a crucial Russian ally.
Russian arms sales to Damascus continue despite the civil disorder and repression in the country.
Towards the end of last month, a Russian warship reportedly visited the Syrian port of Tartus on its way home from an anti-piracy deployment in the Red Sea. It is a reminder that Tartus is the only Russian naval facility outside the territory of the former Soviet Union.Recriminations
So political, strategic and diplomatic concerns explain the Chinese and Russian vetoes. The question is what happens now and how much damage has this diplomatic row in New York caused?
It certainly has been a bitter episode and the recriminations were swift in coming.
The US ambassador to the UN, Susan Rice, said that the US was "outraged" and that opposition to the resolution was "a cheap ruse by those who would rather sell arms to the Syrian regime than stand with the Syrian people."
Western diplomats, though, believe the fallout can be contained.
One source told the BBC that the Syria vetoes were Beijing and Moscow's riposte to the Libya vote and that they should not damage co-operation on other crucial issues like Iran and Yemen.
Now the US and its European allies are likely to try to step up the impact of sanctions on the Assad regime while working with the Arab League, the Gulf Co-operation Council and Turkey to try to deepen their dialogue with Syrian opposition groups.