ISIS is as strong as ever in Syria despite year-long US-led bombing campaign and it could take a DECADE to drive them out of strongholds, claims CIA

  • CIA estimates there are 20,000-30,000 fighters - the same as last August
  • 10,000 have been killed but ISIS replenish their ranks with foreign fighters
  • Bombings weakened Raqqa but it could take a decade to defeat them
  • Well-funded organisation clears $500million (£320million) in oil sales 

A year-long bombing campaign in Syria has had virtually no impact on ISIS numbers, which remain consistently between 20,000 and 30,000, according to the CIA.

The U.S. agency claims the bombings, which have cost billions, have prevented the collapse of Iraq, but the organisation is fundamentally no weaker than it was before.

It's believed more than 10,000 people have been killed but the organisation is able to constantly replenish its ranks with foreign fighters.

No impact: The CIA claims the bombings, which have cost billions, have prevented the collapse of Iraq, but the organisation is fundamentally no weaker than it was before

No impact: The CIA claims the bombings, which have cost billions, have prevented the collapse of Iraq, but the organisation is fundamentally no weaker than it was before

Recovery: It's believed more than 10,000 people have been killed but the organisation is able to constantly replenish its ranks with foreign fighters

Recovery: It's believed more than 10,000 people have been killed but the organisation is able to constantly replenish its ranks with foreign fighters

Fundamentally the same: Numbers are still estimated to be between 20,000 and 30,000, the same as last August when the U.S.-led strikes began

Fundamentally the same: Numbers are still estimated to be between 20,000 and 30,000, the same as last August when the U.S.-led strikes began

Numbers are still estimated to be between 20,000 and 30,000, the same as last August when the U.S.-led strikes began.

They also remain well-funded, with some estimating the group clears up to £320million a year in oil sales and has seized up to $1billion (£641million) from banks in its territories. 

The CIA also concluded that it could take more than a decade to drive ISIS out of strongholds, according to intelligence analysts. 

But the military campaign has put IS under increasing pressure in northern Syria, particularly squeezing its self-proclaimed capital in Raqqa.

IS remains a well-funded extremist army able to replenish its ranks with foreign jihadis as quickly as the US can eliminate them.

Meanwhile, the group has expanded to other countries, including Libya, Egypt's Sinai Peninsula and Afghanistan.

The assessments by the CIA, the Defence Intelligence Agency and others appear to contradict the optimistic line taken by the Obama administration's special envoy, retired general John Allen, who told a forum in Aspen, Colorado, last week that 'Isis is losing' in Iraq and Syria.

'We've seen no meaningful degradation in their numbers,' a defence official said.

IS's staying power also raises questions about the administration's approach to the threat that the group poses to the U.S. and its allies.

Although officials do not believe it is planning complex attacks on the West from its territory, the group's call to Western Muslims to kill at home has become a serious problem, FBI director James Comey and others say.

Yet under the Obama administration's campaign of bombing and training, which prohibits American troops from accompanying fighters into combat or directing air strikes from the ground, it could take a decade to drive IS from its safe havens, analysts say.

The administration is adamant that it will commit no US ground troops to the fight, despite calls from some in Congress to do so.

Money: They also remain well-funded, with some estimating the group clears up to £320million a year in oil sales and has seized up to $1billion (£641million) from banks in its territories

Money: They also remain well-funded, with some estimating the group clears up to £320million a year in oil sales and has seized up to $1billion (£641million) from banks in its territories

The US-led coalition and its Syrian and Kurdish allies on the ground have made some inroads.

IS has lost 9.4 per cent of its territory in the first six months of 2015, according to an analysis by the conflict monitoring group IHS.

And the military campaign has arrested the sense of momentum and inevitability created by the group's stunning advances last year, leaving the combination of Sunni religious extremists and former Saddam Hussein loyalists unable to grow its forces or continue its surge.

'In Raqqa, they are being slowly strangled,' said an activist who fled earlier this year.

'There is no longer a feeling that Raqqa is a safe haven for the group.'

A Delta Force raid in Syria that killed IS financier Abu Sayyaf in May has also resulted in a well of intelligence about the group's structure and finances, US officials say.

His wife, held in Iraq, has been co-operating with interrogators.

Syrian Kurdish fighters and their allies have wrested most of the northern Syria border from IS group.

In June, the US-backed alliance captured the border town of Tal Abyad, which for more than a year had been the militants' most vital direct supply route from Turkey.

The Kurds also took the town of Ein Issa, a hub for IS movements and supply lines only 35 miles north of Raqqa.

As a result, the militants have had to take a more circuitous smuggling path through a stretch of about 60 miles they still control along the Turkish border.

A plan announced this week for a US-Turkish 'safe zone' envisages driving IS out of those areas as well, using Syrian rebels backed by air strikes.

In Raqqa, U.S. coalition bombs pound the group's positions and target its leaders with increasing regularity.

The militants' movements have been hampered by strikes against bridges, and some fighters are sending their families away to safer ground.

In early July, a wave of strikes in 24 hours destroyed 18 flyovers and a number of roads used by the group in and around Raqqa.

Reflecting IS unease, the group has taken exceptional measures against Raqqa residents in the past two weeks, activists say.

The CIA also concluded that it could take more than a decade to drive ISIS out of strongholds, according to intelligence analysts

The CIA also concluded that it could take more than a decade to drive ISIS out of strongholds, according to intelligence analysts

It has moved to shut down private internet access, arrested suspected spies and set up security cameras in the streets.

Patrols by its 'morals police' have decreased because fighters are needed on the front lines, the activists say.

But American intelligence officials and other experts say that in the big picture, IS is hanging tough.

In Iraq, the group's seizure of the strategically important provincial capital of Ramadi has so far stood.

Although US officials have said it is crucial that the government in Baghdad win back disaffected Sunnis, there is little sign of that happening.

American-led efforts to train Syrian rebels to fight IS have produced a grand total of 60 vetted fighters.

The group has adjusted its tactics to thwart a US bombing campaign that tries to avoid civilian casualties, officials say.

Fighters no longer move around in easily-targeted armoured columns but embed themselves among women and children.

They communicate through couriers to thwart eavesdropping and geolocation, the defence official said.

Oil continues to be a major revenue source. By one estimate, IS is clearing 500 million dollars (£320m) a year from oil sales, on top of as much as one billion (£641m) in cash the group seized from banks in its territory.

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