Britain's inability to persuade its fellow EU countries to have weapons supplied to non-Islamist groups in the Syrian opposition was a diplomatic failure waiting to happen. The result is that Britain is left wringing its hands on the sidelines, while Russia's efforts to guide future peace negotiations between the two sides seem increasingly assured and promising. To invert Douglas Hurd's famous formulation, we are punching below our weight: pressing for aggressive solutions which we lack both the muscle to impose ourselves, and the powers of argument to convince our allies to support.
Rewind 18 months and how different the picture looked. Then it was Russia that was in a corner, attacked on all sides for continuing to back Bashar al-Assad's regime and for sabotaging UN efforts to force him either to resign or negotiate. Fresh from our relatively painless involvement in the uprising that brought down Muammar Gaddafi, London, along with Paris and Washington, used all its diplomatic influence to secure a UN resolution that would hasten the Syrian dictator's fall. But Russia (along with China) blocked all those initiatives.
With hindsight there are several reasons why the UK can be grateful for its failure to secure a UN resolution. One is that Syria is not Libya. Libya may be riven by tribal loyalties, but it is largely homogeneous in ethnic and religious terms. Solid democratic governance may take many years to put down roots there, but the sort of basic political stability that is a prerequisite for such a development does not seem completely out of the question.
Syria, by contrast, is a religious and ethnic patchwork. No one can doubt that President Assad's Alawite clique has only clung to power through the ruthless use of force. But there can be no confidence that the fall of Mr Assad would be a prelude to peace. Far more likely, it would be only the first act in a civil war that could make the massacres of the past two years look modest.
In this context, Britain's urge to arm the secular rebel groups while keeping Jihadi ones at arm's length looks naive for a once big power with long experience in the Middle East. Once the weapons are in the theatre, they will remain in play. And if they are in the hands of people we think of as the good guys today, there is no guarantee that they will remain so tomorrow.
Then there is Russia. While Britain, tentatively supported by France, continues to try to hasten a military resolution to the conflict, Moscow has further undermined those efforts by forging ties of its own with some of the Syrian rebel groups, without sacrificing its support for Mr Assad. As a result it is not inconceivable that Moscow will emerge, sooner rather than later, as the only outside power sufficiently trusted by both sides to mediate between them.
Libya may have whetted the appetite of Britain and France for again exercising disproportionate influence in North Africa, but President Hollande has learned quickly from his Mali adventure how treacherous those sands can be. Former Secretary of State Hillary Clinton and Defence Secretary Leon Panetta wanted to supply Syria's rebels with arms, but President Obama, ever more reluctant to commit the US to conflicts like these, vetoed the idea.
William Hague may well be motivated by the sort of humanitarian compulsions that were conspicuously absent from Conservative policy towards Bosnia 20 years ago. But however righteous his motives, yesterday's debacle is a timely reminder that there are severe limits both to the role of force in resolving the conflicts that emerged from the Arab Spring, and to what a small and relatively impecunious country such as Britain can do to bring about peace.