Iraq was not a threat, and the invasion in 2003 was a distraction from the pursuit of Al Qaeda.

That’s the verdict of Baroness Manningham-Buller, who was head of MI5 from 2002-2007. It’s old news now that Tony Blair took us into war on a second front on grounds which were shaky at best. All the same, this bald statement from the former Director General of MI5 should be headline news, not for what it tells us about Tony Blair’s government or the ridiculous contortions of law and intelligence required to get us to war, but for the rugs it pulls from beneath some very large feet.

Back in pre-history, a journalist named Andrew Gilligan asserted that the government had ‘sexed up’ the dossier of published intelligence about Iraq. The government expressed its horror at the very notion, and Gilligan and the BBC were hauled across hot coals. The Hutton Inquiry found that the dossier had not been ‘sexed up’. Gilligan, the chairman, and the director general of the BBC all lost their jobs. The government used the incident as a stick with which to beat the corporation for years. The attempt to cut the BBC’s disobedient news arm down to a more manageable and biddable form continues to this day. (In the past, one prime minister was able to require that the BBC reorder the sequence of footage in the reporting of a riot to make it seem that rioters attacked police, rather than the other way around. Downing Street must long for the good old days.)

But the point isn’t the endless, tedious whinging of affronted politicians at a news organisation which is, in general, pretty solid.

The point is how we conduct inquiries.

Hutton found that the dossier had not been politically influenced. Butler found, in contrast, that more weight had been placed on the intelligence than it could bear. And here is Eliza Manningham-Buller saying:

“Iraq did not present a threat to the UK.

The service advised that [an invasion] was likely to increase the domestic threat and that it was a distraction from the pursuit of al-Qaeda. I understood the need to focus on Afghanistan. Iraq was a distraction.”

And you have Major General Michael Laurie, who was instrumental in drawing up the September dossier, who wrote to the Chilcot inquiry to say that the dossier had been compiled to make the case for war. Sir John Scarlett, in charge of the September dossier, wrote to Downing Street that there was an advantage in “obscuring the fact that in terms of WMD Iraq is not that exceptional.”

If you accept these statements, the question is not whether the intelligence was manipulated for political ends, but how this manipulation was done and at what point. What Eliza Manningham-Buller says appears sets the whole issue on its head: the dossier was not ‘sexed up’; if I understand correctly, it must have been edited or drafted so that what the intelligence services actually believed – that Iraq was not a threat – was hard to find in its pages, leaving only alarming discussions of Iraq’s supposed (and as it turned out non-existent) WMD capacity.

And yet we’re left to piece all this together from scraps. Despite Hutton, Butler, and Chilcot, and a smattering of other reviews, the mechanism of deception has not been exposed. The persons involved in turning black into white – terrifying the British public and parliament into a war which was (whatever you think about the pros and cons of humanitarian military intervention) unnecessary in terms of immediate self-protection and which may have made our security situation worse, and which has proved a massively costly adventure in terms of human life and hard cash – have not been called to account. Ministers and officials have been politely quizzed, and their good faith has been assumed. They have been invited to appear before kindly panels, not subjected to serious questioning on what is arguably the most serious question of our political era.

Our inquiries are toothless and ineffectual, and for as long as that remains the case our democracy is significantly weakened.