The Kurdish soldiers relax half a mile behind the front line where they have been battling Isis forces west of the Syrian town of Ras al-Ayn. The women are in no doubt about why they are fighting.

Nujaan, who is 27 and has been a soldier for four years, says that Isis’s “target is women”. She says: “Look at Shingal [in Iraq] where they raped the women and massacred the men. It is a matter of honour to defend ourselves first, and then our families and lands.” Sitting beside her is Zenya, 22, who adds that she also “is fighting for myself and my family”.

Overhead, the drone of US aircraft is clearly audible and Nujaan reports that there have been several air strikes that morning, as well as ground fighting.

She says that several Kurdish soldiers have been killed and wounded, though she does not know the details. She adds that the YPJ Kurdish women’s militia, to which she belongs, is gradually driving Isis towards the west. She and the other women appear remote and detached from what they are saying, possibly because they are exhausted from days on the front line.

In fact, the push westwards mentioned by Nujaan is of great military and possibly political significance because the Syrian Kurdish armed forces are closing in on a crucial Isis-controlled border crossing point from Syria into Turkey at Tal Abyad. The Syrian Kurds note bitterly that Turkey has closed the crossing points into Kurdish-held territory, but has kept open those used by Isis.

In pictures: The rise of Isis Show all 74 1 /74 In pictures: The rise of Isis In pictures: The rise of Isis Isis fighters Fighters of the Islamic State wave the group's flag from a damaged display of a government fighter jet following the battle for the Tabqa air base, in Raqqa, Syria AP In pictures: The rise of Isis Isis fighters Fighters from Islamic State group sit on their tank during a parade in Raqqa, Syria AP In pictures: The rise of Isis Isis fighters Fighters from the Islamic State group pray at the Tabqa air base after capturing it from the Syrian government in Raqqa, Syria AP In pictures: The rise of Isis Isis fighters Fighters from extremist Islamic State group parade in Raqqa, Syria AP In pictures: The rise of Isis Isis kidnapping A video uploaded to social networks shows men in underwear being marched barefoot along a desert road before being allegedly executed by Isis Getty Images In pictures: The rise of Isis Isis kidnapping Haruna Yukawa after his capture by Isis In pictures: The rise of Isis Isis kidnapping Khalinda Sharaf Ajour, a Yazidi, says two of her daughters were captured by Isis militants Washington Post In pictures: The rise of Isis Isis fighters Spokesperson for Isis Vice News via Youtube In pictures: The rise of Isis A pro-Isis leaflet A pro-Isis leaflet handed out on Oxford Street In London Ghaffar Hussain In pictures: The rise of Isis Isis fighters Isis Jihadists burn their passports In pictures: The rise of Isis Isis controls Syrian Aid A man collecting aid administered by Isis in Syria In pictures: The rise of Isis Isis controls Syrian Aid A woman collecting aid administered by Isis in Syria In pictures: The rise of Isis Isis controls Syrian Aid Local civilians queue for aid administered by Isis. Since it declared a caliphate the group has increasingly been delivering services such as healthcare, and distributing aid and free fuel In pictures: The rise of Isis Iraq crisis Iraqi security forces detain men suspected of being militants of the Isis group in Diyala province In pictures: The rise of Isis Iraq crisis Mourners carry the coffin of a Shi'ite volunteer from the brigades of peace, who joined the Iraqi army and was killed during clashes with militants of the Isis group in Samarra, during his funeral in Najaf In pictures: The rise of Isis Iraqi refugees An Iraqi Shiite Turkmen family fleeing the violence in the Iraqi city of Tal Afar, west of Mosul, arrives at a refugee camp on the outskirts of Arbil, in Iraq's Kurdistan region In pictures: The rise of Isis Isis leader Abu Bakr al-Baghdadi A photograph made from a video by the jihadist affiliated group Furqan Media via their twitter account allegedly showing Isis leader Abu Bakr al-Baghdadi delivering a sermon during Friday prayers at a mosque in Mosul. Abu Bakr al-Baghdadi declared an Islamist caliphate in the territory under the group's control in Iraq and Syria In pictures: The rise of Isis Islamic extremists destroying mosques in Iraq Shiite's Al-Qubba Husseiniya mosque explodes in Mosul In pictures: The rise of Isis Islamic extremists destroying mosques in Iraq Smoke and debris go up in the air as Shiite's Al-Qubba Husseiniya mosque explodes in Mosul. Images posted online show that Islamic extremists have destroyed at least 10 ancient shrines and Shiite mosques in territory - the city of Mosul and the town of Tal Afar - they have seized in northern Iraq in recent weeks In pictures: The rise of Isis Islamic extremists destroying mosques in Iraq A bulldozer destroys Sunni's Ahmed al-Rifai shrine and tomb in Mahlabiya district outside of Tal Afar In pictures: The rise of Isis Iraq crisis Iraqi security forces celebrate after clashes with followers of Shiite cleric Mahmoud al-Sarkhi, in front of his home in the Shiite holy city of Karbala, 50 miles (80 kilometers) south of Baghdad In pictures: The rise of Isis Iraq crisis Iraqi security forces arrest a follower of Shiite cleric Mahmoud al-Sarkhi after clashes with his followers in the Shiite holy city of Karbala, 50 miles (80 kilometers) south of Baghdad In pictures: The rise of Isis Iraq crisis Iraqi security forces arrest a follower of Shiite cleric Mahmoud al-Sarkhi at his home after clashes with his followers in the Shiite holy city of Karbala, 50 miles (80 kilometers) south of Baghdad In pictures: The rise of Isis Iraq crisis Iraqi security forces arrest a follower of Shiite cleric Mahmoud al-Sarkhi after clashes with his followers in the Shiite holy city of Karbala, 50 miles (80 kilometers) south of Baghdad In pictures: The rise of Isis Iraq crisis A vehicle burns in front of a home of a follower of Shiite cleric Mahmoud al-Sarkhi after clashes with his followers in the Shiite holy city of Karbala, 50 miles (80 kilometers) south of Baghdad In pictures: The rise of Isis Iraqi refugees An Iraqi woman holds her exhausted son as over 1000 Iraqis who have fled fighting in and around the city of Mosul and Tal Afar wait at a Kurdish checkpoint in the hopes of entering a temporary displacement camp in Khazair In pictures: The rise of Isis Iraqi refugees Displaced Iraqi women hold pots as they queue to receive food during the first day of the Islamic holy month of Ramadan, at an encampment for displaced Iraqis who fled from Mosul and other towns, in the Khazer area outside Irbil, north Iraq In pictures: The rise of Isis Isis fighters in Syria A militant Islamist fighter waving a flag, cheers as he takes part in a military parade along the streets of Syria's northern Raqqa. The fighters held the parade to celebrate their declaration of an Islamic "caliphate" after the group captured territory in neighbouring Iraq In pictures: The rise of Isis Isis fighters in Syria Isis fighters wave flags as they take part in a military parade along the streets of Syria's northern Raqqa province Reuters In pictures: The rise of Isis Isis fighters in Syria Isis fighters travel in a vehicle as they take part in a military parade along the streets of Syria's northern Raqqa province In pictures: The rise of Isis Isis fighters in Syria Fighters from the Isis group during a parade with a missile in Raqqa, Syria. Militants from an al-Qaida splinter group held a military parade in their stronghold in northeastern Syria, displaying U.S.-made Humvees, heavy machine guns, and missiles captured from the Iraqi army for the first time since taking over large parts of the Iraq-Syria border In pictures: The rise of Isis Isis fighters in Syria Isis fighters during a parade in Raqqa, Syria In pictures: The rise of Isis Isis fighters in Syria Fighters from the Isis group during a parade in Raqqa, Syria. Militants from the splinter group held a military parade in their stronghold in northeastern Syria, displaying U.S.-made Humvees, heavy machine guns, and missiles captured from the Iraqi army for the first time since taking over large parts of the Iraq-Syria border In pictures: The rise of Isis Isis fighters in Syria Isis fighters hold a military parade in their stronghold in northeastern Syria In pictures: The rise of Isis Isis fighters in Syria Isis fighters during a parade in Raqqa, Syria In pictures: The rise of Isis Isis fighters in Syria A member loyal to the Isis waves an Isis flag in Raqqa In pictures: The rise of Isis Iraq crisis Iraqi anti-government gunmen from Sunni tribes in the western Anbar province march during a protest in Ramadi, west of Baghdad. The United Nations warned that Iraq is at a "crossroads" and appealed for restraint, as a bloody four-day wave of violence killed 195 people. The violence is the deadliest so far linked to demonstrations that broke out in Sunni areas of the Shiite-majority country more than four months ago, raising fears of a return to all-out sectarian conflict In pictures: The rise of Isis Iraq crisis Iraqi security forces hold up a flag of the Isis group they captured during an operation to regain control of Dallah Abbas north of Baqouba, the capital of Iraq's Diyala province, 35 miles (60 kilometers) northeast of Baghdad In pictures: The rise of Isis Isis fighters in Iraq Isis fighters parade in the northern city of Mosul In pictures: The rise of Isis Iraq crisis Volunteers, who have joined the Iraqi army to fight against the predominantly Sunni militants from the radical Isis group, demonstrate their skills during a graduation ceremony after completing their field training in Najaf In pictures: The rise of Isis Iraq crisis Kurdish Peshmerga troops fire a cannon during clashes with militants of the Isis group in Jalawla, Diyala province In pictures: The rise of Isis Lieutenant General Qassem Atta speaks during a press conference Iraqi Prime Minister's security spokesman, Lieutenant General Qassem Atta speaks during a press conference about the latest military development in Iraq, in the capital Baghdad. Iraqi forces pressed a campaign to retake militant-held Tikrit, clashing with jihadist-led Sunni militants nearby and pounding positions inside the city with air strikes in their biggest counter-offensive so far In pictures: The rise of Isis A police station building destroyed by Isis fighters An exterior view of a police station building destroyed by gunmen in Mosul city, northern Iraq. Iraq's new parliament is expected to convene to start the process of setting up a new government, despite deepening political rifts and an ongoing Islamist-led insurgency. Iraqi President Jalal Talabani issued a decree inviting the new House of Representatives to meet and form a new government In pictures: The rise of Isis Isis fighters in Iraq Smoke billows from an area controlled by the Isis between the Iraqi towns of Naojul and Tuz Khurmatu, both located north of the capital Baghdad, as Iraqi Kurdish Peshmerga forces take part in an operation to repel the Sunni militants In pictures: The rise of Isis Iraqi refugees An elderly Iraqi woman is helped into a temporary displacement camp for Iraqis caught-up in the fighting in and around the city of Mosul in Khazair In pictures: The rise of Isis Iraqi refugees An Iraqi Christian woman fleeing the violence in the village of Qaraqush, about 30 kms east of the northern province of Nineveh, cries upon her arrival at a community center in the Kurdish city of Arbil in Iraq's autonomous Kurdistan region In pictures: The rise of Isis Iraqi refugees An Iraqi woman, who fled with her family from the northern city of Mosul, prays with a copy of the Quran AP In pictures: The rise of Isis Isis fighters in Iraq The body of an Isis militant killed during clashes with Iraqi security forces on the outskirts of the city of Samarra Reuters In pictures: The rise of Isis Iraq crisis Iraqi civilians inspect the damage at a market after an air strike by the Iraqi army in central Mosul EPA In pictures: The rise of Isis Iraq crisis Members of the Al-Abbas brigades, who volunteered to protect the Shiite Muslim holy sites in Karbala against Sunni militants fighting the Baghdad government, parade in the streets of the city AP In pictures: The rise of Isis Iraq crisis Shia tribesmen gather in Baghdad to take up arms against Sunni insurgents marching on the capital. Thousands have volunteered to bolster defences AFP/Getty In pictures: The rise of Isis Iraq crisis A van carrying volunteers joining Iraqi security forces against Jihadist militants. Prime Minister Nuri al-Maliki announced the Iraqi government would arm and equip civilians who volunteered to fight AFP/Getty In pictures: The rise of Isis Iraq Fighters of the Isis group parade in a commandeered Iraqi security forces armored vehicle down a main road at the northern city of Mosul In pictures: The rise of Isis Iraq An Islamist fighter, identified as Abu Muthanna al-Yemeni from Britain (R), speaks in this still image taken undated video shot at an unknown location and uploaded to a social media website. Five Islamist fighters identified as Australian and British nationals have called on Muslims to join the wars in Syria and Iraq, in the new video released by the Isis In pictures: The rise of Isis Iraq Al-Qa’ida inspired militants stand with captured Iraqi Army Humvee at a checkpoint belonging to Iraqi Army outside Beiji refinery some 250 kilometers (155 miles) north of Baghdad. The fighting at Beiji comes as Iraq has asked the U.S. for airstrikes targeting the militants from the Isis group. While U.S. President Barack Obama has not fully ruled out the possibility of launching airstrikes, such action is not imminent in part because intelligence agencies have been unable to identify clear targets on the ground, officials said In pictures: The rise of Isis Iraq Militants attacked Iraq's main oil refinein Baiji as they pressed an offensive that has seen them capture swathes of territory, a manager and a refinery employee said In pictures: The rise of Isis Iraq Militants from the Isis group parading with their weapons in the northern city of Baiji in the in Salaheddin province In pictures: The rise of Isis Iraq A smoke rises after an attack by Isis militants on the country's largest oil refinery in Beiji, some 250 kilometers (155 miles) north of the capital, Baghdad. Iraqi security forces battled insurgents targeting the country's main oil refinery and said they regained partial control of a city near the Syrian border, trying to blunt an offensive by Sunni militants who diplomats fear may have also seized some 100 foreign workers In pictures: The rise of Isis Iraq Militants of the Isis group stand next to captured vehicles left behind by Iraqi security forces at an unknown location in the Salaheddin province. For militant groups, the fight over public perception can be even more important than actual combat, turning military losses into propaganda victories and battlefield successes into powerful tools to build support for the cause In pictures: The rise of Isis Iraq An injured fighter (C) from the Isis group after a battle with Iraqi soldiers at an undisclosed location near the border between Syria and Iraq In pictures: The rise of Isis Iraq Fighters from the Isis aiming at advancing Iraqi troops at an undisclosed location near the border between Syria and Iraq In pictures: The rise of Isis Iraq Fighters from the Isis group taking position at an undisclosed location near the border between Syria and Iraq In pictures: The rise of Isis Iraq Fighters from the Isis group inspecting vehicles of the Iraqi army after they were seized at an undisclosed location near the border between Syria and Iraq In pictures: The rise of Isis Iraq One Iraqi captive, a corporal, is reluctant to say the slogan, and has to be shouted at repeatedly before he obeys Sky News In pictures: The rise of Isis Iraq Iraqi captives held by the extremists Sky News In pictures: The rise of Isis Iraq Iraqi captives held by the extremists Sky News In pictures: The rise of Isis Iraq Militants of the Isis group force captured Iraqi security forces members to the transport In pictures: The rise of Isis Iraq Militants of the Isis group transporting dozens of captured Iraqi security forces members to an unknown location in the Salaheddin province ahead of executing them In pictures: The rise of Isis Iraq A major offensive spearheaded by Isis but also involving supporters of executed dictator Saddam Hussein has overrun all of one province and chunks of three others In pictures: The rise of Isis Iraq Militants of the Isis group executing dozens of captured Iraqi security forces members at an unknown location in the Salaheddin province In pictures: The rise of Isis Iraq Isis militants taking position at a Iraqi border post on the Syrian-Iraqi border between the Iraqi Nineveh province and the Syrian town of Al-Hasakah In pictures: The rise of Isis Iraq Isis rebels show their flag after seizing an army post AFP/Getty Images In pictures: The rise of Isis Iraq Isis militants waving an Islamist flag after the seizure of an Iraqi army checkpoint in Salahuddin Getty Images In pictures: The rise of Isis Iraq Demonstrators chant slogans as they carry al-Qa’ida flags in front of the provincial government headquarters in Mosul, 225 miles (360 kilometers) northwest of Baghdad. In the week since it captured Iraq's second-largest city, Mosul, a Muslim extremist group has tried to win over residents and has stopped short of widely enforcing its strict brand of Islamic law, residents say. Churches remain unharmed and street cleaners are back at work

But now Tal Abyad, the northern end of the road that leads straight to Raqqa, the Isis Syrian capital, is threatened by a pincer movement by Kurds advancing from both the east and west. Some are coming from the battered town of Ras al-Ayn in the main Kurdish canton of al-Jazeera and, from the west, forces are advancing from Kobani, which withstood a four-and-a-half-month Isis siege.

Sehanok Dibo, adviser to Saleh Muslim and Asya Abdullah, the leaders of the PYD (Democratic Union Party), the ruling party in the three Kurdish cantons on the Turkish border that make up the statelet of Rojava, told The Independent in an interview that Tal Abyad is the next Kurdish military target. “We are 18km from Tal Abyad in the east and 20km [from Tal Abyad] in the west,” he said. “We hope to liberate it soon.” If this happens, it will be a serious blow to Isis, and also to Turkey, which will see even more of the Syrian side of its southern frontier controlled by Kurds. Mr Dibo takes it as a matter of proven fact that “Turkey supports Daesh [the Arabic acronym for Isis used in Iraq and Syria]”.

Female fighters of the YPJ (women’s defence units) in Rojava, a Kurdish controlled area of Syria (Hisham Arafat)

He stresses that he is not part of the Syrian Kurdish military command structure, but his opinion about Isis’s future strategy is significant because the Syrian Kurds are the only military force in Iraq and Syria consistently to defeat the jihadis. He says: “I think their next target will be Dayr Az Zawr [the provincial capital on the Euphrates which is partly held by Syrian government forces] because the people in the city are Sunni Arabs and tribal. Isis will get support there.”

In the longer term, Mr Dibo expects Isis and other jihadist groups, such as Jabhat al-Nusra, to try to capture the half of Aleppo that is still held by President Bashar al-Assad and the Syrian army. He sees Mr Assad’s military strength ebbing by the day. Despite savage rivalries between Isis and Jabhat al-Nusra, he believes that in most respects they are just the same. “They are the children of al-Qaeda,” he says.

The leaders of the Syrian Kurds are jubilant at the moment because of their victory over Isis at Mount Abdulaziz last week. Trucks full of cheering soldiers are returning from the front. The Kurds in this north-east corner of Syria know, somewhat to their own surprise, that, encircled by enemies though they may be, they are living in the safest part of Syria. The territory behind the front line where Nujaan and Zenya are fighting is full of farmers bringing in the wheat harvest and without the undercurrent of terror you find in the rest of Syria.

Of course, the greater safety in this triangular-shaped Kurdish enclave only stands out because of the contrast with everywhere else on the borders of the “Islamic State”. But, for the moment, there are no car bombs, kidnappings, bandit gangs at check points or fear of massacre. The PYD and its armed wing, the YPG (People’s Defence Units), have an effective monopoly of power here, as it does in the two other Kurdish cantons on the Turkish frontier that gained de facto autonomy when the Syrian army withdrew in July 2012. Though its militarised rule is not popular with all Kurds, its militiamen and women do provide genuine protection – unlike the Syrian or Iraqi armies.

It may not last and it has not come easily. Ras al-Ayn, a town of about 30,000 people, still looks shattered by heavy fighting in 2012 and 2013 when it was at the centre of clashes between the Kurds and extreme jihadists led by Jabhat al-Nusra, then the Syrian branch of Isis and now the official affiliate of al-Qaeda in Syria. Everywhere in this shabby little town, there are bombed-out ruins and surviving walls peppered with the pockmarks made by machine-gun bullets.

Ibrahim and Jamil, two middle-aged PYD representatives, give a guided tour of their town, pointing to the border crossing with Turkey across which Jabhat al-Nusra-led forces poured on 11 November 2012. They say that “at first we welcomed them because they were against the Assad regime and then we were shocked to find they were all jihadis”.

They enforced compulsory attendance at the mosque, stole Christian houses and attacked and killed all who opposed them. Captured officers from the ruling Allawi sect were massacred and the regime in Damascus responded with random bombing that killed many civilians and levelled rows of houses.

The battle for Ras al-Ayn went on from November 2012 to July 2013 and has similarities with the struggle within the opposition to the regime between the jihadis and secular forces. The difference is that, here in Ras al-Ayn, the anti-jihadis were well armed and militarily experienced, since the PYD is effectively the Syrian branch of the Kurdistan Workers Party (PKK) that has been fighting the Turkish army since 1984.

Ibrahim says the final stage of this complex battle, which had many ceasefires interrupted by new bouts of street fighting, came on 16 July 2013. Rojna, leader of the YPJ women’s fighters, was buying material for uniforms in the bazaar, when she and her guards were attacked by al-Nusra militants infuriated by the sight of a female military leader. “It was then we decided to finally drive them out,” says Ibrahim.