Jonathan Eyal, Europe Correspondent In London

Targeting terrorist leaders still a viable option

Abu Bakr al-Baghdadi, leader of the self-proclaimed Islamic State in Iraq and Syria (ISIS), has apparently resurfaced alive after he was rumoured to have been killed in a recent United States-led air strike.

However, the terrorist organisation which he heads released only a voice recording of his latest rants but no pictures, an indication that he may have been wounded in the attack.

Yet, even if his survival is proven beyond doubt, "Caliph Ibrahim" - as he likes to be called - knows that it's only a matter of time before another missile delivered from a US drone or airplane seeks to end his existence.

The assassination of individual terrorist leaders is now central to many states' national security strategies. What was once an exceptional and highly unusual tactic is now commonplace.

But does the strategy of killing terrorist leaders - referred to in Western intelligence circles as "decapitation" - actually work?

Does it produce the required results, namely a drastic reduction in terrorist activity?

The answers are by no means conclusive, although the arguments for and against targeting individual terrorists are more evenly balanced than people assume them to be.

Attempts to assassinate leaders are as old as humanity. The reigns of many kings and emperors ended suddenly by poison-laced food, knives or a bullet.

But in the modern context of fighting terrorism, it was Israel which pioneered the decapitation strategy from the late 1960s, and particularly since the 1972 massacre of its sportsmen attending the Munich Olympic Games, when a distinct Israeli intelligence unit was created for this purpose.

Most of the world's governments - the US' included - initially shunned this Israeli tactic.

All their objections conveniently disappeared after the Sept 11, 2001 terrorist attacks on the US, when attacks against terrorist leaders not only proliferated, but were also incorporated into America's military strategy.

Precise statistics about the volume and success rates of such operations are not easy to come by.

The best effort in this regard was made by political scientist Patrick Johnston of the Rand Corporation, a big American think-tank.

He identified about 110 direct assassination attempts against top terrorist leaders in the decade after the Sept 11 attacks, and calculated that around 40 per cent of these were successful.

At first sight, not a bad score card, at least in purely military terms.

Still, one has to factor in the reality that, for each recorded assassination strike against a terrorist leader, many more were aborted at an early stage, so the statistics are an understatement.

Nor do the figures convey the sheer magnitude of the effort required from governments.

Literally thousands of intelligence analysts in key countries around the world do nothing but follow every step of such "high-value targets", piecing together the tiniest scraps of information about where top terrorists may be hiding, guessing where they may be going next and distinguishing between the decoy "doubles" and their real human targets.

Intelligence chiefs also have to make sure that they have the necessary firepower near their intended targets on an almost continuous basis, since an opportunity to kill a terrorist leader may suddenly present itself for a few minutes, and then disappear for years to come.

All decapitation strategies are far from cheap: They require substantial human and financial investment and divert considerable intelligence resources.

Yet curiously for a strategy which is both expensive and often commands public attention, there is no consensus on whether it actually works. Most academics argue that the strategy is at best irrelevant, at worse counterproductive in fighting terrorism.

In the aftermath of the assassination of their leaders, terrorist organisations are prone to retaliate, and that only fuels a more vicious spiral of violence.

That was what happened in 1996, when Israel assassinated Yahya Ayyash, the chief bomb-maker for Hamas also known as "The Engineer".

The Palestinian organisation staged four retaliatory bombings on buses in Israel, in which more than 50 civilians died.

Assassinating top terrorists, critics argue, creates new "heroes" and "martyrs" and actually aids terrorist organisations in their recruitment.

It also risks bringing to the fore much worse people.

That was the case with the decapitation of the leadership of the Chechen separatists in Russia, which was replaced by more determined terrorists.

The same happened to the Provisional Irish Republican Army in Britain, where the successive generations of leaders were even more pathological in their violence.

The strategy can also be illegal, since it effectively entails decisions taken by Western politicians or civil servants to execute people without due process, even if the targets are citizens of the same country.

That was what happened in 2011 to Anwar al-Awlaki, a US citizen and talented recruiter for Al-Qaeda, who was killed by a missile fired from an American drone in what must surely count as a classic case of US extrajudicial killing.

Most importantly, critics argue, there is no evidence that decapitating terrorist commanders brings about the death of the organisations they lead.

"Even if organisations are weakened after the killing or arrest of their leaders, they tend to survive, regroup and continue carrying out attacks," writes Assistant Professor Jenna Jordan of the Georgia Institute of Technology, who earlier this year authored an exhaustive study on the aftermath of the assassination of terrorist bosses.

But much of this criticism is neither comprehensive nor entirely persuasive.

For no military strategist or government has ever argued that eliminating top terrorists provides the "silver bullet" to the problem of terrorism.

Nor has anyone suggested that terrorist leaders are completely irreplaceable, and that their assassination would lead to the disintegration of their organisations.

Still, there is plenty of evidence that terrorist organisations are not like any corporation, and replacing terrorist leaders is not similar to appointing a new chief executive officer for a company, if only because terrorist organisations have no formal succession procedures.

As Major Bryan Price from the US Military Academy perceptively pointed out, it took Al-Qaeda over 45 days to respond to Osama bin Laden's death by naming Ayman al-Zawahiri as his successor, despite the fact that al-Zawahiri served as Osama's deputy for years.

Everyone knew that Osama was the target of every intelligence agency, so Al-Qaeda should have expected this eventuality.

In reality, assassinating leaders does have consequences for every terrorist organisation, even those which are well established.

The Kurdistan Workers' Partyterrorised Turkey for decades, but went silent the moment its legendary leader Abdullah Ocalan was captured by Turkish elite forces in 1999.

Furthermore, the mere fact that terrorist leaders know they are being targeted constricts their behaviour, even if they never end up being killed. The current leaders of Hamas physically moved out of Gaza to evade Israeli drones, something that must have hampered their ability to act.

Nor are the arguments that drone attacks against terrorist leaders create "martyrs" or help recruitment as persuasive as they sound, as they are based on the assumption that these leaders are universally loved, and that their demise would embolden their followers into worse acts of violence.

The reality is that most of the intelligence information which leads to the tracking and assassination of key terrorist leaders comes from informers within the terrorist organisations, an indication that current terrorist leaders are not as universally followed as they would like to pretend.

And as to martyrdom?

Analysts have argued that the 2004 assassination of Sheikh Ahmed Yassin, the wheelchair-bound spiritual leader of Hamas, would propel the organisation into overall leadership of Palestine. Yet, a decade later, nothing of the kind has happened.

Many also believed that Osama's killing would elevate him to the status of the Muslim world's most revered figure.

But T-shirts emblazoned with his face have long been out of fashion, and none of the misguided youth who volunteer to fight for ISIS even knows who Osama was, or what he stood for.

None of this suggests that the assassination of terrorist leaders raises no troubling moral dilemmas.

Nor is there any doubt that the "decapitation" of terrorist organisations provides no long-term solution to the problem of terrorism.

Just look at Israel, which has applied the strategy for the longest time, but still faces an ever-growing security challenge.

Still, there is no doubt that targeting terrorist leaders remains a viable option in fighting the terrorist scourge.

The men who plot violence and have no compunction in taking the lives of others should not be too surprised if their lives also end suddenly, and violently.