The US and Iran have no Alliance in the Struggle Against ISIS

US and Iranian military involvement in Iraq against ISIS does not amount to an 'alliance'. Both powers find themselves temporarily aligned against the spread and threat of ISIS for different reasons. For Iran it is about maintaining the Sh'ite 'axis of resistance' against Sunni insurgents in Syria and Iraq.

For the US, its deployment of drones and military advisors is mostly about helping check ISIS so that it could not threaten Baghdad or the south where attacks by ISIS could threaten global oil prices and even to blowback into the land of its main ally in Saudi Arabia.

It was Saudi Arabia, along with Qatar, that in 2012 and throughout 2013 supported and bankrolled the most effective Sunni insurgents in Syria and created the space within which ISIS could gain ground and control over oil installations to fund its activities.

Throughout 2014 Saudi Arabia has moved away from the policy under pressure from Washington and the obvious fact the policy failed in so far as ISIS broke with the Free Syria Army it had previously been aligned with back in 2013 in its struggle against Kurdish seperatists.

That allowed Assad to roll back the FSA from Damascus, leading the Syrian National Council and some intelligence observers to start claiming he had been funding ISIS himself through buying oil from them. But that, of course, would not change the fact that most past funding for came from donors in the Gulf states.

In turn, due to the threat of blowback Saudi Arabia and Qatar sought to accuse each other of backing the wrong sort of Sunni jihadists. One senior Qatari official stated, “ISIS has been a Saudi project.”. Other GCC members have been critical of Qatar for 'playing with fire' and continuing to back Islamist groups with links to Al Qaida.

So even if Iran and the US are seen to be in 'alliance', they are not. Iran's regional policy would be in ruins if Iraq fell into the hands of Sunnis as it was under Saddam Hussein. The construction of a Shi'ite gas pipeline via Iraq and Syria, agreed on back in 2011, would be impossible.

Likewise, the US, along with Qatar and Saudi Arabia, are not going to stop opposing that plan by supporting Sunni insurgents in Syria against Assad. Qatar wants a Qatar-Turkey pipeline that would supply European markets and that is backed especially by Britain and France.

Iran is already under sanctions and the last thing Washington would like would be a lucrative gas pipeline through which it could export gas to the Eastern Mediterranean, interests it has in common which Russia which is backing Assad so as ensure gas supplies are controlled by it and its regional the US, partners.