As British Prime Minister David Cameron is set to make a statement to Parliament today on the need to join the air campaign in Syria ahead of a vote next week on extending Britain's air strikes there, The Straits Times Europe correspondent Jonathan Eyal weighs the arguments for and against such strikes.
British government ministers have never claimed that air strikes are a panacea against threats emanating from Syria. But they have argued that, in the absence of a broader foreign military involvement to stop the Syrian civil war, air power can still achieve useful objectives.
The first objective is to target the bases of the so-called Islamic State in Iraq and Syria (ISIS) terrorist organisation. It is pointless to fight ISIS in Iraq - as a Western-led coalition of nations which includes Britain has done for the past two years - only to see the terrorists seek refuge and supplies across the border in neighbouring Syria. ISIS militants "don't recognise a border between Iraq and Syria, and neither should we", says British Prime Minister David Cameron.
Destroying ISIS also requires the elimination of the organisation's lifelines, such as its supply and recruitment routes and the oil smuggling businesses which provide ISIS with cash, all of which flow through Syria.
French President Francois Hollande has instructed his air force to do so and, according to British officials, the results are encouraging.
Air power, military commanders in London acknowledge, cannot stop the Syrian government from waging war on its people. But it can limit the intensity of the bloodshed. It was only the threat of the use of air power that persuaded Syrian President Bashar al-Assad to give up most of his chemical weapons in a deal brokered in 2013. It was also the selective use of air strikes which limited the Syrian military's ability to inflict an even higher rate of casualties on its civilian population.
And London is anxious to point out that the use of strikes from the air - usually delivered by "drones", or unmanned aerial vehicles - is already playing an important role in eliminating some of the notorious terrorists, such as Mohammed Emwazi, otherwise known as "Jihadi John", the Briton filmed beheading hostages in various ISIS propaganda videos.
British diplomats admit that the legal case for air strikes in Syria is not watertight. Still, they point to a number of arguments which indirectly justify it. Last week, the United Nations Security Council unanimously adopted a resolution branding ISIS "a global and unprecedented threat to international peace and security". While that resolution does not explicitly authorise the use of force, it clearly calls on all UN member states to "take all necessary measures" under international law and the UN Charter.
One clear principle of international law is the right of collective self-defence, and it is this tenet that countries can use in deploying their air power: The recent terrorist attacks in France were hatched and organised by ISIS, and it is obvious that further attacks are being planned. "I firmly support the action that President Hollande has taken to strike," said Mr Cameron. "It is my firm conviction that Britain should do so too," he added at a joint news conference after his meeting with Mr Hollande earlier this week.
Finally, the civil war in Syria has already killed a quarter of a million civilians, and displaced a further eight million, some of whom are the refugees now streaming into Europe. Doing nothing about the conflict in Syria is, therefore, no longer an option, argue British officials, for the consequences of the Syrian civil war are already felt in Europe.
British Prime Minister David Cameron has had to grapple with domestic opposition to military involvement in the Syrian civil conflict since war started in that Middle Eastern country four years ago.
Mr Cameron became the first British leader in almost a century to lose a vote on a war question, when Parliament rejected his arguments for the use of air power against Syrian government forces in August 2013.
Much of this opposition stemmed from memories of Britain's involvement in the US-led invasion of Iraq a decade previously, a war now widely regarded by the electorate as a grave strategic mistake and a tragic waste of human lives. As Mr Ed Miliband, then leader of the opposition Labour Party, put it: "Britons want to learn the lessons of Iraq; they want things done in the right way."
Yet finding the "right way" to persuade a sceptical public has not been easy for Mr Cameron. He has had to fend off criticism that the use of air power to overthrow Libyan leader Muammar Gaddafi in 2011 - a decision for which he was personally responsible - produced no long- lasting beneficial outcomes: Libya is now mired in war, just as vicious as the one prevailing in Syria.
Mr Cameron's critics also challenged him to prove how he can ensure that air strikes will not kill civilians or generate "collateral damage". "Air strikes in populated areas caused 3,165 civilian deaths and injuries in the year up to August," claims Action on Armed Violence. The non-governmental organisation did not explain how it arrived at such a precise figure, but the belief that air strikes are imprecise is widespread.
Nor was the British leader able to explain how air strikes can distinguish between the "good" and "bad" guys on the ground, between people who should be supported and those who must be opposed. A bewildering collection of up to 100 different paramilitary formations now operate in Syria. Discriminating between them is a fool's errand, claim the critics.
An influential British parliamentary committee of inquiry released a critical report earlier this month, arguing that "no decision" on the use of force in Syria should be taken until the government presents a "coherent international strategy" to defeat the Islamic State in Iraq and Syria (ISIS) terrorist organisation and end the country's civil war.
Critics also point out that Britain currently has only eight aircraft operating in Iraq on similar missions against ISIS. That's hardly a big contingent, and it's unlikely that London would be able to do more than just double that number of jets, should a future operation against Syria be authorised.
And then, there are lingering questions about what an air campaign would achieve. Air power has influenced the conduct of previous wars, but has never settled any conflict. If Britain wants to help stop the war in Syria, there is no escape from sending troops on the ground, and from putting its soldiers in harm's way.
But since Mr Cameron has ruled this out, a political solution is the only alternative, argue opponents. "In our view, the dreadful Paris attacks make the case for a far more urgent international effort to reach a negotiated settlement of the Syrian civil war," argues Mr Jeremy Corbyn, the current opposition Labour leader, who plans to commit his party to vote against air strikes.
This article was first published on November 26, 2015.
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