Manasfi's motives for joining the struggle against President Bashar al-Assad are unknown, but Syria has become the number one theatre for international "jihad".
During the 1980s, radical Muslims travelled to Afghanistan to fight the Soviet occupation; later their spotlight fell variously on Chechnya, Kashmir, Iraq and Afghanistan again.
Today, their prime goal is Mr Assad's downfall. As a secular dictator who leads a regime dominated by the Alawite sect -- which radical Sunnis regard as heretical -- he ranks high in the catalogue of infamy for any follower of al-Qaeda's ideology.
The fact that this places al-Qaeda on the same side as the West is uncomfortable but not unprecedented: the same was true in Afghanistan during the anti-Soviet struggle.
Ayman al-Zawahiri, the al-Qaeda leader, is based thousands of miles from Syria in the borderlands of Pakistan.
Nonetheless, he probably regards the struggle against Mr Assad as his first priority. But how much of a threat does this pose to Western security?
Hundreds of Britons, many of Syrian or other Arab origin, have gone to fight Mr Assad. Worryingly, between 50 and 100 were already known to the British security services for their extremist sympathies.
As long as they are part of the insurrection in Syria, they pose no threat at home. The question is whether they will return as battle-hardened jihadists, able and willing to carry out attacks in Britain?
Recent experience provides the only possible guide. Afghanistan and Pakistan became the epicentre for jihad after the terrorist attacks on September 11 -- and a steady flow of dangerous people moved between Britain and the subcontinent.
When Iraq took over as the main focus after the invasion of 2003, British residents travelled there to fight.
But not many returned -- and those who did failed to carry out any attacks, except the botched bombing of Glasgow airport in 2007.
Why did so few come back from Iraq compared with Afghanistan and Pakistan? The answer partly lies in the ease of travel between Britain and the subcontinent, with hundreds of thousands of people making this journey every year, mainly for innocent reasons.
Will Syria follow the pattern of Iraq or Afghanistan? No one can tell for the moment, but there is one ominous fact: when travelling via Turkey, rebel-held Syria is less than a day's journey from Britain.
By David Blair