Last week’s disclosures from the Chilcot Inquiry into the Iraq war are pretty strong stuff, whichever way you cut it. They include both evidence from a senior defence intelligence official that the September 2002 dossier was “sexed-up” to make a case for war and a landmark publication of three policy papers from MI6 in late 2001, discussing the pros and cons of “regime change”.

It has been suggested that the author of the papers, identified by the Inquiry as “SIS4” is Sir Mark Allen, who left MI6 to work for BP. As I have written on the Iraq Inquiry Digest website, it is not clear that concealing SIS4’s identity is entirely in line with the Inquiry’s protocols.

As some newspapers have noted, one of SIS4’s papers includes, at the beginning of a paragraph headed “why move?”, a statement that: “The removal of Saddam remains a prize because it could give new security to oil supplies.”

This comes hard on the heels of revelations from campaigner Greg Muttitt’s freedom of information requests, which showed the Labour government pitching before the 2003 invasion to get a “slice of the action” for oil companies like BP and Shell. It also represents an embarrassment for Sir John Chilcot, who was part of the 2004 Butler Review. The Butler report said the following:

“It has frequently been alleged that the real motivation behind the decision to go to war in Iraq was a desire to control Iraq’s oil supplies. This issue does not fall within our terms of reference and we did not take evidence specifically on it. We did, however, review JIC assessments on the security of oil supplies issued in the period 2000-2003, in which such a motivation did not feature. We also think it improbable that such an objective or motivation, if it existed, would not have been apparent in the large volume and wide range of policy and intelligence papers that we examined. We saw no evidence that a motive of the British Government for initiating military action was securing continuing access to oil supplies.”

So the Butler Review saw a “large volume and wide range of policy and intelligence papers” but saw no evidence that securing continuing access to oil supplies was even a part of the government’s motivation. If the contents of SIS4’s paper are not such evidence, you have to wonder what would be.

It has to be asked whether the paper was withheld from the Butler Review or whether Butler, Chilcot and the rest of the review team felt the need to keep its contents from the rest of us.