THE expansion of the military element of the coalition against the Islamic State (IS) forces in Iraq and Syria, with Canada ready to commit jet fighters to it, has failed to stop jihadist advances in several areas. At the same time, the complexity of the crisis is growing. Kurds in Iraq and Syria are angry at Turkey's failure to enter the conflict to save Kurdish population centres, such as Kobani on the Syrian-Turkish border, from IS attack.

The expansion of air strikes seems certain to cement the grim pattern of IS revenge on captured foreigners. The murder of the British volunteer aid worker Alan Henning is not likely to be the last of its kind in a war that, by the admission of political and military leaders, is likely to last several years. The killing of Mr Henning, a taxi driver from Eccles who had dedicated his life to helping people in need in Syria, has had a profound effect on people around the world. Prayers for his family have been said in churches and mosques in many countries.

Speaking on Radio 4's Sunday programme, the Bishop of Manchester, Dr David Walker, said that "in Christian theology we have the word 'martyr' for somebody who is witness to the values, the faith they live by - who lets the good that lies in their heart come out to such an extent that they are killed for it." Every death of this kind, he said, "brings us back to the story of the cross and to understanding that our Christian faith is actually rooted in somebody who was killed for the good he was doing".

Dr Walker also had a message for IS: "You've lost your power to shock. That happened maybe two or three executions ago. Now you sicken us. You and your brutality have no part in the world going forward." The Archbishop of Canterbury had earlier tweeted: "Alan Henning's memory will last, he gave his life serving people far away with nobility & love. Pray for his family's strength and courage."

For the indigenous Christians of Syria and Iraq, many of whom are now homeless, the foreseeable future looks bleak. Although most welcome the campaign of air strikes to stop further IS advances, some - such as the Roman Catholic Archbishop of Irbil, the Most Revd Bashar Warda - believe that this measure alone will not keep Christians safe. "It may be strange for a Catholic bishop to say 'Please, we need more force,'" he told the BBC, "but it's really self-defence. I can see my people are dying. It's terribly painful. We have to defend ourselves."

Given the likelihood that the duration of the anti-IS campaign will be measured in years rather than months, Arab states that have joined the campaign are contemplating measures to prevent jihadist ideology taking root in their societies. This is particularly the case in Saudi Arabia, where the conservative Wahhabi Salafist Islamic tradition is followed. Critics of the kingdom say that IS is merely a violent arm of the same ideology.

King Abdullah of Saudi Arabia, in a speech on Sunday to mark this year's Hajj pilgrimage to Mecca, spoke of the need for Muslims to be tolerant of others and to promote dialogue. By so doing, they would "prevent bloodshed and avoid disunity, ignorance, and extremism". But this goal would not be achieved, he said, "unless we create the necessary and appropriate atmosphere. Taking care in bringing up children and guiding the young is essential for dialogue. We are all responsible for guiding them, and we hope that the scholars, preachers, and thinkers of the Islamic world will present role-models for the young by showing them the appropriate way to engage in dialogue." The King said that Muslims themselves needed to be shown "the tolerance and moderation of the Islamic religion".

Saudi Arabia also believes that the defeat of IS in Iraq and Syria will not be possible before a change of regime in Damascus - taking the view that the Syrian government at very least ignored the rise of the jihadists and may even have encouraged them.

The fact that the main goal of Western states is the elimination of IS rather than bringing down the Bashar al-Assad regime is just one of the many complexities in the current crisis. Another is the growing hostility that Kurds feel towards Turkey. While Ankara opposes the independence ambitions of Turkish and Syrian Kurdish factions, it has developed close political and economic ties with Kurds in northern Iraq. But the failure of Turkey to come to their help when IS forces advanced on their region in June is a source of extreme bitterness.

Likewise, Turkey's silence as Kobani came under jihadist attack seemed to confirm in the minds of Kurds as a whole that Ankara's hostility to Kurdish separatism surpassed its desire to try to prevent humanitarian disasters. One possible outcome of all this could be the collapse of the fragile truce between Ankara and Turkey's main Kurdish separatist group, the PKK.

Kurds from different communities and religious backgrounds are holding a Solidarity Gathering this Saturday, at 5.30 p.m. at St Marylebone Parish Church, in London, at a ceremony hosted by the Rector, Canon Stephen Evans.

IN A further blow to the morale of Christians in the Middle East, a Syrian Franciscan friar and about 20 other Christians have been abducted at gunpoint from the small village of Knayeh, close to Syria's border with Turkey.

The Latin Patriarch of Jerusalem, the Most Revd Fouad Twal, said that Fr Hanna Jallouf OFM, of the Franciscan Custody of the Holy Land, who is a parish priest, and the other Christians were taken away on Sunday night, allegedly by members of the al-Qaeda-affiliated al-Nusra Front. Nothing has been heard from their abductors since then.

Several nuns in Knayeh are said to have found shelter among families in the village.

The Roman Catholic news agency Fides, quoting the Apostolic Vicar of Aleppo in Syria, the Rt Revd Georges Abou Khazen OFM, said that among the 20 Christians taken were "young people, both boys and girls".

Fr Jallouf, a Syrian, has lived in Knayeh for 12 years, after serving in the Jordanian capital, Amman. Knayeh, which is in Idlib province, has been under the control of jihadist Islamists for more than a year - initially, members of IS, and, since January, of the al-Nusra Front.

Restrictions had been put on the movement of Christians, and crosses and other symbols removed from public places.

In areas of Syria under Islamist domination, Christians are frequently accused of supporting and collaborating with the government of President Bashar al-Assad, and this was believed

to have been the case with Fr Jallouf and his congregation in Knayeh.

An Italian Jesuit, Fr Paolo Dall'Oglio, is still missing, after being kidnapped in Raqqa, in northern Syria, in July last year (News, 2 August 2013).