As the leaders of the world's biggest industrialised democracies gather in the once unlikely setting of Enniskillen in Northern Ireland, their sights are set on another intractable and potentially long-running conflict: Syria.
Everyone agrees something must be done but the question is what exactly their intentions are.
The Americans say they now accept the Assad regime has used chemical weapons and wish to increase their own support for the rebels accordingly.
David Cameron has always seemed keen to arm Assad's opponents but faces opposition from within his own party and cabinet, not to mention from his own security advisors who seem far from enticed by the prospect.
So what will actually happen? What is the reality behind the rhetoric?
I am told that President Obama is likely to specify before he leaves here what he means by arming the rebels.
There is genuine uncertainty as to which way he will go, but the opposition forces already have access to plenty of weapons through the Saudis and what they want is the kind of sophisticated military kit that the Russians are giving to the Syrian government.
It would certainly be a brave step on the part of a President who has always given the impression of being reluctant to get involved anywhere.
Much less likely is any change of stance from David Cameron. He is said to believe that the 'moderate' rebels in Syria can be bolstered and supported, but most expect our help to come in the form of further aid and training rather than military equipment.
At least, for now...