Intelligence reports examined and now released by the Chilcot inquiry appear to confirm Islamic State (IS, formerly ISIS/ISIL) was created by the Iraq war, a view now apparently backed by Britain's Tory Foreign Secretary Philip Hammond.

The reports from the Joint Intelligence Committee (JIC), which were previously classified, tell the story of the security services’ increasing concern that the war and occupation was fuelling ever more extremism in Iraq.

The evidence also appears to debunk repeated claims by former PM Tony Blair that IS began in the Syrian civil war and not Iraq, positioning the brutal group’s rise clearly within Iraq’s borders.

The Chilcot findings were backed up Thursday by serving Foreign Secretary Phillip Hammond. He told The Foreign Affairs Committee “many of the problems we see in Iraq today stem from that disastrous decision to dismantle the Iraqi army and embark on a program of de-Baathification.”

“That was the big mistake of post-conflict planning. If we had gone a different way afterwards we might have been able to see a different outcome,” he said.

Hammond conceded that many members of Saddam’s armed forces today filled top roles in IS.

“It is clear a significant number of former Baathist officers have formed the professional core of Daesh [IS] in Syria and Iraq and have given that organization the military capability it has shown in conducting its operations.”

The documents show that by 2006 – three years into the occupation – UK intelligence chiefs were increasingly concerned about the rise of Sunni jihadist resistance to the Western-backed regime of Shia President Nouri Al-Maliki.

A March 2007 JIC report warned Al-Qaeda in Iraq, which it terms AQ-I, had “no shortage of suicide bombers. AQ-I is seeking high-profile attacks. We judge AQ-I will try to expand its sectarian campaign wherever it can: suicide bombings in Kirkuk have risen sharply since October when AQ-I declared the establishment of the notional ‘Islamic State of Iraq’ (including Kirkuk).”

Many leading Al-Qaeda figures had been pro-regime Baathists and members of the former Iraqi Army disbanded by the occupation. They are broadly accepted to have later formed the basis for IS.

The report describes AQ-I as being “in the vanguard.”

“Its strategic main effort is the prosecution of a sectarian campaign designed to drag Iraq into civil war” at the head of a number of other Sunni militia groups.

“We judge its campaign has been the most effective of any insurgent group, having significant impact in the past year, and poses the greatest immediate threat to stability in Iraq. The tempo of mass-casualty attacks on predominantly Shia targets has been relentless,” the spies argue.

Chillingly, an earlier report from 2006 appears to echo some of the realizations made late in the Vietnam War that there were also strong elements of nationalism driving the insurgency.

“They claimed that the label ‘jihadist’ is becoming increasingly difficult to define: in many cases distinctions between nationalists and jihadists are blurred. They increasingly share common cause being drawn together in the face of Shia sectarian violence.”

The reports appear to suggest that the conditions also somewhat echo the Afghanistan war, which by that time was already underway, in that the anti-coalition forces displayed a mix of ideological and economic drivers to resist the occupation.

“Their motivation is mixed: some are Islamist extremists inspired by the AQ agenda, others are simply hired hands attracted by the money,” the spies warn.

The religious sectarianism involved, however, was distinctly Iraqi and reflected the power battle between the deposed Sunni forces and the US-installed Shia regime which replaced it.

They also appeared to believe that AQ-I was composed of local and not, as was claimed at the time, foreign fighters.

“We judge Al-Qaida in Iraq is the largest single insurgent network and although its leadership retains a strong foreign element, a large majority of its fighters are Iraqi.

“Some are drawn in by the opportunity to take on Shia militias: the jihadists’ media effort stresses their role as defenders of the Sunni,” the report concludes.

Prophetically, even before IS began to germinate in Iraq, one now-declassified Foreign Office memo from January 2003 warned “all the evidence from the region suggests that coalition forces will not be seen as liberators for long, if at all. Our motives are regarded with huge suspicion.”