<p>As Jeremy Corbyn offers his party a free vote over military action in Syria what are the arguments for and against the UK extending its air campaign against Islamic State militants? </p> <h2><strong>Why are we debating airstrikes in Syria?</strong> </h2> <p>The government <a href="http://www.theguardian.com/politics/2015/nov/30/commons-vote-syria-airstrikes-labour-jeremy-corbyn-isis">is planning to hold a Commons vote on Wednesday</a> on extending Britains bombing campaign against Isis from Iraq to Syria as public alarm about the extremist groups continuing strength increases in the wake of the attacks in Paris. <a href="http://www.theguardian.com/politics/2015/nov/26/david-cameron-publishes-case-for-syria-airstrikes">David Cameron set out the moral and security case for bombing Isis in Syria</a> in the Commons last week, saying it was morally unacceptable to leave the US, France and other allies to carry the burden. If not now, when? he asked MPs. </p> <p>The issue has exposed deep divisions in the Labour party. In 2013 Labours opposition helped inflict a surprise defeat against Cameron and his plans to launch airstrikes against the regime of the Syrian president, Bashar al-Assad, over his use of chemical weapons. More than two years later many in the parliamentary Labour party, including half the shadow cabinet, are much more convinced by the case for airstrikes in Syria against Isis, which has seized and held territory amid the civil war. Corbyn, the party leader, is opposed.<br /></p> <h2><strong>Who is currently bombing Isis in Syria?</strong></h2>  <figure class="element element-image" data-media-id="9b47b1e72eb6225f9ed466d9c768fb439e348514"> <img src="https://media.guim.co.uk/9b47b1e72eb6225f9ed466d9c768fb439e348514/0_0_3000_1800/1000.jpg" alt="A French Mirage 2000 fighter prepares to take off for an airstrike on Raqqa." width="1000" height="600" class="gu-image" /> <figcaption> <span class="element-image__caption">A French Mirage 2000 fighter prepares to take off for an airstrike on Raqqa.</span> <span class="element-image__credit">Photograph: Abaca/PA</span> </figcaption> </figure>  <p>There have been almost 3,000 airstrikes against Isis targets in Syria since a <a href="http://www.theguardian.com/world/2014/sep/23/us-launches-air-strikes-against-isis-targets-in-syria">US-led campaign began in September 2014</a>. More than 95% of these have been conducted by the United States, according to the <a href="http://airwars.org/index.html">US monitoring group Airwars</a>. From the start, Americas Gulf allies  Saudi Arabia, Jordan, the United Arab Emirates, Bahrain and Qatar  have all taken part in some of the airstrikes. In <a href="http://www.theguardian.com/world/2015/sep/27/france-launches-first-airstrikes-isis-syria">September, France joined the campaign</a>, and has since stepped up its airstrikes in Syria in the wake of the Paris attacks with a massive attack on the Isis stronghold of Raqqa in the north-east of the country. </p> <p>In September, Russia also launched airstrikes against terrorist groups in Syria. Fewer than 10% of its initial strikes were against Isis targets, the majority have been against anti-Assad groups, some backed by the US and Turkey. </p> <h2><strong>What is the current state of Isis in Syria?</strong></h2>  <figure class="element element-image" data-media-id="22f323226d3af9bff42897e06856ca912ee2f280"> <img src="https://media.guim.co.uk/22f323226d3af9bff42897e06856ca912ee2f280/0_66_3300_1980/1000.jpg" alt="A member of Isis carries the flag in Raqqa." width="1000" height="600" class="gu-image" /> <figcaption> <span class="element-image__caption">A member of Isis carries the flag in Raqqa.</span> <span class="element-image__credit">Photograph: Reuters</span> </figcaption> </figure>  <p>Isis controls large swaths of north-east Syria including its stronghold of Raqqa and a number of lucrative gas and oil fields in the east. It controls most of the territory along the banks of the Euphrates including strategically important dams. It only controls one of Syrias top 10 cities by population  Deir Ezzor near the border with Iraq. </p>  <figure class="element element-interactive interactive" data-interactive="https://interactive.guim.co.uk/embed/iframe-wrapper/0.1/boot.js" data-canonical-url="https://interactive.guim.co.uk/uploader/embed/2015/11/isis-insyria/giv-32650z0Ug8rbMNt0r/" data-alt="Areas of Syria currently controlled by Islamic State fighters."> <a href="https://interactive.guim.co.uk/uploader/embed/2015/11/isis-insyria/giv-32650z0Ug8rbMNt0r/">Areas of Syria currently controlled by Islamic State fighters.</a> </figure>  <p>The number of people fighting for Isis is more difficult to gauge. In 2014 the CIA estimated its strength at up to <a href="http://www.usatoday.com/story/news/world/2015/07/29/air-campaign-kills-15000-isis-militants-pentagon-iraq-syria/30750327/">31,500 fighters in both Iraq and Syria.</a> Since airstrikes began the US says it has killed at least 10,000 militants in both countries, though the arrival of fresh fighters from outside the country may not have significantly hit its overall strength. Some have estimated there are <a href="http://www.longwarjournal.org/archives/2015/06/us-claims-10000-islamic-state-fighters-killed-since-start-of-air-campaign.php">up to 50,000 Isis fighters in the region.</a> </p> <h2><strong>How strong are the anti-Isis forces?</strong> </h2> <p>Citing British intelligence, Cameron said there were about <a href="http://www.theguardian.com/world/2015/nov/30/70000-syrian-fighters-david-cameron-islamic-state-airstrikes">70,000 non-extremist Syrian opposition fighters who could help fight Isis</a>. What he didnt emphasise is that these fighters are split into at least 100 to 120 different groups, with various aims, and differing in size from thousands to just 100 to 200 members. So far they have not shown much interest in focusing on Isis, being too preoccupied fighting Assads Syrian army.</p> <aside class="element element-rich-link element--thumbnail"> <p> <span>Related: </span><a href="http://www.theguardian.com/world/2015/nov/30/70000-syrian-fighters-david-cameron-islamic-state-airstrikes">Who are these 70,000 Syrian fighters David Cameron is relying on?</a> </p> </aside>  <h2><strong>Are anti-Isis groups in the Syrian opposition moderate? </strong></h2> <p>The most effective groups militarily in the opposition are among the most hardline. Two groups currently dominant are Jaish al-Islam and Ahrar al-Sham, which have a <a href="http://blogs.new.spectator.co.uk/2015/11/yes-there-are-70000-moderate-opposition-fighters-in-syria-heres-what-we-know-about-them">combined strength of 27,500 fighters</a>, according to analyst Charles Lister from the Brookings Doha centre. Both of these groups and perhaps a small number of others are definitely not natural western allies, no doubt about it. But they vehemently oppose [Isis] being in Syria and have fought it successfully in the past  with far better results than our currently favoured allies, the Kurds, he points out. </p> <p>One of the other most powerful forces is the al-Qaida linked group, Jabhat al-Nusra, which has also been banned by the US. Both Jabhat al-Nusra and Ahrar al-Sham have been heavily involved in ousting Isis fighters from Syrias Idlib province and the Aleppo countryside in the north.</p> <h2><strong>How strong is the Free Syrian Army? </strong></h2>  <figure class="element element-image" data-media-id="2d5c2b2a98691be5d7308aa82669210b7c3d39ce"> <img src="https://media.guim.co.uk/2d5c2b2a98691be5d7308aa82669210b7c3d39ce/0_0_3500_2099/1000.jpg" alt="Free Syrian Army." width="1000" height="600" class="gu-image" /> <figcaption> <span class="element-image__caption">Free Syrian Army.</span> <span class="element-image__credit">Photograph: Zohra Bensemra/Reuters</span> </figcaption> </figure>  <p>The alliances of moderate opposition fighters in Syria is constantly shifting, but many still fight under the broad banner of the Free Syrian Army (FSA). They control much of the territory in and around the western Syrian cities of Hama and Homs. They include groups such as Tajamu AlaAzza and Liwa Suqor al-Jebel which have received CIA training and weapons. Groups allied with the FSA also control areas around Syrias southern border with Jordan. But after years of disunity and faltering advances the <a href="http://www.theguardian.com/world/2015/oct/01/whos-who-syrian-conflict-russian-airstrikes">influence of the FSA is on the wane</a>, according to the Guardians Syria specialist, Martin Chulov. </p> <h2><strong>Who is fighting whom? </strong></h2>  <figure class="element element-interactive interactive" data-interactive="https://interactive.guim.co.uk/embed/iframe-wrapper/0.1/boot.js" data-canonical-url="https://interactive.guim.co.uk/uploader/embed/2015/11/iraq-andsyriaforces/giv-32650xDYvL4IqXqUd/" data-alt="Competing forces in Syrias civil war."> <a href="https://interactive.guim.co.uk/uploader/embed/2015/11/iraq-andsyriaforces/giv-32650xDYvL4IqXqUd/">Competing forces in Syrias civil war.</a> </figure>  <p>There are a series of global, regional and religious conflicts being played out in Syria that make the conflict so potentially explosive and complicated. These are the main battles: <br /></p> <ul> <li><strong>Assad v the opposition</strong></li> <li><strong>Sunni v Shia: </strong>President Assad and many of those in his inner circle are Alawites  a minority sect in Syria that is a branch of Shia Islam. Shia forces involved in the Syrian civil war on Assads side include Irans elite Quds force under Qassem Suleimani; the Lebanese group Hezbollah, and the Shia militias of Iraq.<br /></li> <li><strong>Kurdish battle for independence</strong>: Kurds represent about 10% of Syrias population and live mostly along its border with Turkey and northern Iraq. They have established control of a large part of this area since the withdrawal of Syrian government forces in 2012. The US has used airstrikes to help Kurds hold on to their gains against the advance of Isis. This has alarmed Turkey, which has its own Kurdish population. In the infamous battle for Kobane, Kurdish fighters resisted Isis with help of US airstrikes, while Ankara stood by and refused to allow Kurdish fighters to cross into Syria. Turkey has bombed Kurdish guerrillas in Syria, who it says were aiding fighters on its territory.</li> </ul> <h2><strong>What is the UKs position?</strong></h2> <p>Whether the UK should get involved in this conflict is the subject of a debate that has exposed serious divisions in the Labour party, but also unease among some government backbenchers. The governments case is built on the argument that such action would disrupt the ability of Isis to organise attacks in Europe, while containing the extremist group by denying it territory and access to finance, primarily through oil exports. </p> <h2><strong>Will bombing disrupt Isiss ability to carry out terrorist attacks in Europe?</strong></h2> <p>The investigation into the Paris attacks showed that at least half the perpetrators had undergone some kind of centrally organised training with Isis.<br /></p> <p>The experience of the fight against al-Qaida suggests that precise targeting of training camps and leaders reduced its capacity to strike western capitals. Documents recovered by US navy seals at Osama bin Ladens compound showed that drone strikes had made it near impossible for al-Qaida to host and train foreign fighters in the main area under its control, the Federally Administered Tribal Areas (Fata) in western Pakistan.</p> <p>However, there are also signs that Isis has learned from al-Qaidas mistakes, and now avoids structured training camps, preferring to live and organise in residential buildings among civilians.<br /></p> <p>In Raqqa, Deir Ezzor and Mosul, Isis is living almost totally among civilians, so you cant hit them, said Rami Abdurrahman, head of the Syrian Observatory for Human Rights. He pointed out that thousands of foreign jihadi had managed to travel to and from <a href="http://www.theguardian.com/world/syria">Syria</a> for the past few years through Turkey and questioned the wisdom of now trying to stop militants with bombs when they could have been stopped with tighter border controls.</p> <p>The Paris conspirators, including the presumed ringleader, Abdelhamid Abaaoud, were able to travel between Belgium, France and Syria while the US-led airstrikes targeting Isis command and control were in full swing.</p> <h2><strong>Can bombing contain Isis?</strong></h2>  <figure class="element element-image" data-media-id="5ebae0f5bdd9e09a125eee29ef5ab69e88941e88"> <img src="https://media.guim.co.uk/5ebae0f5bdd9e09a125eee29ef5ab69e88941e88/0_0_3300_1981/1000.jpg" alt="Residents inspect a damaged site from what activists said were airstrikes carried out by the Russian air force in Nawa city, Deraa." width="1000" height="600" class="gu-image" /> <figcaption> <span class="element-image__caption">Residents inspect a damaged site from what activists said were airstrikes carried out by the Russian air force in Nawa city, Deraa.</span> <span class="element-image__credit">Photograph: Alaa Al-Faqir/Reuters</span> </figcaption> </figure>  <p>US-led airstrikes helped stop Isis capturing key strategic points such as Kobane on the Turkish border, and the Kurdish stronghold of Irbil. In neighbouring Iraq, they were instrumental in preventing the fall of Baghdad when Isiss power was at its zenith. UK air support also played a role in the liberation of the Iraqi town of Sinjar by Kurdish peshmerga forces.</p> <p>Counter-terrorism experts say that such defeats damage Isiss international appeal to foreign jihadis, which depends on the image of a constantly expanding caliphate.</p> <p>However, further gains against Isis will require something that has so far eluded the western coalition, a working alliance with other Sunni rebel groups in Syria. </p> <p>Hassan Hassan, a Syria expert at the Chatham House thinktank and co-author of Isis: Inside the Army of Terror, said that persuading other Sunni armed groups to fight Isis as well as the Assad regime may ultimately be the key to success, but that requires a great deal of local knowledge and political commitment.</p> <p>The answer is not dropping more bombs, Hassan said. The answer is to find a way to support these groups on the ground. Its not about money or even weapons. It is about helping them with tactics and an overall strategy that has been missing.</p> <p>He argued that the expensive US efforts to build an anti-Isis rebel movement failed because it worked with the wrong people and lacked long-term political commitment. The success of any British military contribution, Hassan added, will lie in the UKs ability to break out of the constraints of Washingtons current strategy.</p> <p>The recent emphasis on striking tankers carrying Isis oil exports is likely to dent the groups vast financial resources but may not affect its immediate fighting capacity. Hassan said Isis scored its most significant victories before it captured the oil fields.</p> <h2><strong>Could bombing Isis backfire?</strong></h2>  <figure class="element element-image" data-media-id="b54dde83f81630e9faea646bf7f5ed8986fa4460"> <img src="https://media.guim.co.uk/b54dde83f81630e9faea646bf7f5ed8986fa4460/0_0_1955_1173/1000.jpg" alt="Footage from the Russian Defence Ministry of an explosion after airstrikes carried out by Russian air force on Idlib." width="1000" height="600" class="gu-image" /> <figcaption> <span class="element-image__caption">Footage from the Russian defence ministry of an explosion after airstrikes carried out by Russian air force on Idlib.</span> <span class="element-image__credit">Photograph: AFP/Getty Images</span> </figcaption> </figure>  <p>Airstrikes on Raqqa last week are reported to have killed at least 12 people, including five children, when bombs fell near a school. It was not clear whether the bombs were dropped by Russian, American or French planes.</p> <p>The number of civilian casualties from Russian bombardment is far higher than the number caused by American and French airstrikes, said Wael Aleji, spokesman for the Syrian Network for Human Rights. This can be attributed to technology. The Russians use more dumb bombs and have less advanced guidance systems.<br /></p> <p>In his memorandum to the Commons, Cameron pointed to the enhanced precision of the UKs Brimstone missile as one of the contributions Britain can make to the air campaign. But avoiding civilian casualties will also depend on good intelligence. </p> <p>One of the worst civilian tolls attributed by human rights activists to a US strike was on 1 May <a href="http://www.theguardian.com/world/2015/may/02/death-toll-syria-climbs-us-led-air-strike">near Aleppo</a>, where more than 60 civilians were said to have been killed, perhaps more than half of them children. Abdurrahman said: We think they got the wrong information. They thought it was Isis, but it wasnt.</p> <p>As it becomes harder to find genuine Isis targets, as the terrorist group gets better at melting in with the surrounding population, the civilian toll is likely to rise. And Syrians on the receiving end are unlikely to make the distinction between British warplanes and Russian bombers sent by Assads chief ally.</p> <p>This is likely to generate support for Isis, or at least create indifference among local people, Hassan said. These are the risks of unintended consequences.</p> <h2>Where does the public stand on bombing Syria?</h2> <p>Antiwar demonstrators gathered outside Downing Street and other locations across the UK on Saturday, but a YouGov poll for the Times found that the majority of voters (59%) back airstrikes in Syria. There was clear backing even among Labour voters with 52% saying they would approve of airstrikes compared with 26% against. But Labour members, especially those who voted for Corbyn in the leadership contest, were overwhelming opposed to the move. Meanwhile Labour said a random sample of <a href="http://www.theguardian.com/politics/2015/nov/30/majority-labour-members-oppose-syria-isis-airstrikes-poll-says">full individual Labour party members showed 75% were against UK bombing in Syria</a>, 13% were in favour and 11% were undecided.</p>  <figure class="element element-tweet" data-canonical-url="https://twitter.com/dylsharpe/statuses/671236829291655168">  <blockquote class="twitter-tweet"><p lang="en" dir="ltr">Diane Abbott keeps saying the public are opposed to air strikes on Syria. There is absolutely no evidence for this <a href="https://t.co/p6eahXmqbZ">pic.twitter.com/p6eahXmqbZ</a></p>&mdash; Dylan Sharpe (@dylsharpe) <a href="https://twitter.com/dylsharpe/status/671236829291655168">November 30, 2015</a></blockquote>  </figure>  <p> Do you have any further questions about military action in Syria? What else would you like to know? Share your questions in the comments below, and well answer a selection.</p> <ul> <li>This article was amended on 2 December 2015. It originally stated that Ahrar al-Sham was linked to the Muslim Brotherhood and classed by the US as a proscribed organisation. This is not the case and has been deleted.<br /></li> </ul>