The European Union is headed for a showdown over calls by Britain and France to arm Syria's rebels that are likely to run into a wall of resistance at talks Friday between the bloc's foreign ministers.
What weapons would be supplied and to whom? What would be the consequences? Might the arms fall into the hands of radical jihadist fighters?
The debate will be sharp when the ministers, as they do every six months, meet for two days of informal talks aimed at fine-tuning Europe's bid to speak with a single voice on the world stage.
As the Syrian conflict runs into a third year with more than 70,000 dead and one out of five Syrians in need of assistance to survive, whether or not to lift an arms embargo in order to equip the insurgents will highlight the rifts in EU ranks.
Paris and London forced the issue on an EU summit only a week ago but found little to no support for their bid to tip the balance in favour of the Free Syrian Army, notably with ground-to-air missiles against air attacks by President Bashar al-Assad's forces.
Italy and Slovenia were said to be the only voices in support.
"Europe will certainly supply weapons, ammunition and money to the forces fighting Assad," said analyst Gianni Riotta of the European Council on Foreign Relations think tank amid reports Britain, France and the United States are already training Syrian rebels.
"But it won't be the EU institutions acting in a centrally coordinated way." This would be the work of individual nations or groups, he said, adding: "Again the EU will fail to punch with a single fist."
After sharp divisions over the Balkans in the 1990s and Iraq in 2003, Britain and France first went it alone in Libya in 2011 but finally won the support of more than a dozen nations for a NATO-led no-fly zone that was backed by the UN.
"France and Britain traditionally act as a motor. When they commit and engage others will follow," said Vivian Pertusot of the IFRI think-tank.
But at last week's summit German Chancellor Angela Merkel expressed "a number of concerns" and Austria warned it would pull hundreds of its UN forces from the disputed Golan Heights between Israel and Syria if the embargo was scrapped.
At a meeting three weeks ago, the two European defence giants pressed their EU partners to ease the arms embargo to allow the supply of non-lethal equipment to the rebels, Britain immediately pledging armoured vehicles and protective clothing.
The arms embargo is part of a package of tough wide-ranging sanctions that expires May 31 and must be renewed unanimously by all 27 EU states.
While no final decision is expected at the Dublin talks, they will provide an opportunity for what is expected to be a sharp debate on the pros and cons, with a final decision likely near the end of May.
"If the embargo falls each state will regain the sovereign right to decide for itself," said French foreign ministry spokesman Philippe Lalliot.
"We would never violate the embargo," said a French source speaking on condition of anonymity. "Paris wants to maintain the sanctions but lift the embargo."
The move by the two nations comes as hopes dim both of a political solution or military breakthrough in Syria.
"We are more likely to see political progress if people can see the Syrian opposition as a credible and strengthening force," said British Prime Minister David Cameron.
But the West remains dubious over the fragmented Syrian opposition, with the US military's top officer General Martin Dempsey this week saying Washington had only an "opaque" view of the rebels.
Top US diplomat John Kerry said the United States would not oppose moves by some European countries to arm Syrian rebels but Washington has fears the weapons could end up in the hands of Al-Qaeda linked militants.