THE allied attacks on IS in Iraq and Syria will force the organisation to unite with al-Qaeda, resulting in a potentially nightmare scenario for the west, a terror expert has predicted.

The Fiscal Times quoted Iraqi writer Hisham al-Hashimi, who says the rhetoric between the two groups has softened markedly since they split apart in February.

“The attacks by the United States and her allies will unite the two groups,” al-Hashimi said.

“I have been monitoring al-Qaeda’s leaders’ rhetoric towards [IS leader] al-Baghdadi. They are getting softer and softer …. The Islamic State, regardless of how big or small it becomes, will come back to its mother: al-Qaeda,” he added.

Already there are signs of unification between the two groups.

Back in June, the UK Telegraph reported that al-Qaeda’s Syrian offshoot al-Nusra had pledged its loyalty to IS at a strategic point on the Iraqi/Syrian border.

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And in another ominous move, the Pakistani Taliban has vowed to send fighters to help IS, even though its formal ally is al-Qaeda and not the Islamic State group.

“We will keep on sending Mujahideen to help IS militants. We completely support them, because we think that this organisation was made to serve Islam,” said Shahidullah Shahid, spokesman for the Tehreek-e-Taliban Pakistan (TTP).

The Pakistani Taliban “are less popular than Daesh (ISIS) is in Pakistan, because there’s a sense of success, of Sunni empowerment,” explained Salman Shaikh, director of the Brookings Doha Center.

“There is an ideological symmetry there ... and what galvanises them is that they are both under attack from the United States.”

Terror experts have warned that the lightning rise of IS is turning it into a magnet for Muslim extremists, drawing disillusioned youth from around the world to its ranks.

Yezid Sayigh, senior associate with the Carnegie Middle East Center in Beirut, warned the United States must be wary of fuelling anger in a region where anti-US sentiment always bubbles close to the surface.

“The critical impact of ISIL which we should all keep our eyes on is not Pakistan, it’s what is going to start happening in Jordan and maybe in Lebanon where there are very large receptive audiences,” Sayigh said.

“If this air campaign goes on for a long while without a clear political strategy, without clear results, it’s not just in Iraq and Syria that we will see the consequences.

“But at the moment Western leaders don’t seem to have their eyes on that ball.”

The United States has made undermining IS’s toxic ideology one of the pillars of its fight, praising moderate Muslim leaders who have denounced the group’s barbarity as nothing to do with Islam.

“ISIL has had success in growing and building capacity, recruiting, growing and financing,” acknowledged State Department spokeswoman Jen Psaki.

But “the alternative is not to do nothing,” she added, defending the US-led air strikes against militant positions in both Iraq and Syria.

Some argued that there is danger of over-hyping the dangers posed by IS, with Western intervention being “a great recruiting sergeant.”

“Some perspective is needed, even while the dangers that IS presents are acknowledged,” wrote Nick Witney, a senior policy fellow with the European Council on Foreign Relations.

“Neither Iraq nor Syria can be whole again until the group is defeated. But its main threat is ideological: the group’s self-proclaimed role as champion of Islam is enormously attractive for psychopaths, extremists, opportunists, and those who harbour resentments against the West.”