It took seven years to produce but Sir John Chilcot's inquiry at least had clarity at the end about what happened when Tony Blair's New Labour Government joined George W. Bush in invading Iraq to topple Saddam Hussein.
In pronouncing that the UK chose to join an invasion before the peaceful options for coping with Hussein had been exhausted, that there was no imminent threat to Britain in March 2003 and that Blair presented arguments about the threat with a certainty that was not justified, Chilcot's language was direct. This was a report with a spine, not the whitewash some soldiers' families had feared.
The planning and preparations for Iraq after Hussein, it declared, were "wholly inadequate". The military preparations were rushed and confused and the Blair government failed to achieve its objectives.
Before the invasion was launched in March 2003 we saw the biggest demonstrations ever known on London's streets from the Stop The War protesters. Critics of the war will take comfort from Sir John Chilcot's verdict that the intelligence did not establish beyond all doubt that Hussein was continuing to produce chemical and biological weapons.
The impression left by first readings of the massive report is that what the government said and did was predetermined not by what the bare intelligence had suggested but by what people took to be the Prime Minister's wishes -- the wishes of a Prime Minister who had told President George W. Bush in July 2002 that he was with him "whatever".
The inquiry indicated concerns too about the decision-making process, especially in how Blair effectively decided himself that there was a legal basis for war, a subject on which his Attorney General changed his mind after a visit to the United States.
Blair was famous for his "sofa-style" government with small groups of intimates and he conceded in the wake of the report that perhaps he should have taken more decisions formally through his Cabinet. Chilcot complained that in Blair's time the risks of military action were never properly identified or exposed to ministers.
So what will change as a result of Chilcot? Not Tony Blair. Although he looked gaunt and strained and spoke with emotion in his response Wednesday, he insisted there were two things he would never do. He would not apologize tor toppling Hussein, and he would not admit that the lives that were lost had been lost in vain. The world was a better and safer place without the dictator who had used chemical weapons against his own people, he said.
Blair said he was sorry for mistakes and he understood the grief of families who had lost loved ones. But he had done his duty from the best of motives. While Chilcot suggested that Blair overestimated his ability to influence Bush, the former Prime Minister insisted that, from the moment of 9/11 on, the right place for Britain was alongside its strongest ally.
Some things have changed already. Reporting to Parliament on Chilcot, Prime Minister David Cameron emphasized that he had set up a National Security Council to deal with questions like military action and claimed a changed culture in which civil servants and advisers were not scared of voicing doubts about a course of action. But having himself intervened in Libya, he insisted that Chilcot's criticisms did not mean that military intervention was always wrong or that Britain should now shrink away from a world role.
As for the Iraqi people, whose sufferings since the invasion have been on an altogether different scale, the Chilcot Inquiry will have been a matter of bland indifference.
The one man who did apologize to them directly was Labour Party Leader Jeremy Corbyn. In a Westminster speech he apologized to the Iraqi nation on behalf of his party for the launching of an offensive which he said was the most serious foreign policy calamity for 60 years, costing hundreds of thousands of lives.
Corbyn also apologized to British families for the loss or injury of soldiers who should, he said, never have been sent to war and to the British people for what he called the undermining of democracy by the way in which the decision to go to war was taken by Blair in secret meetings with George Bush.
The Chilcot Inquiry's 2.6 million words will be combed through for some time to come, especially by those who are suggesting that the bereaved families might yet seek legal action against Blair in the courts.
But they are unlikely to make the slightest difference to the most dramatic result of the 2003 invasion -- the wave of brutal terrorism which was unleashed by reducing Iraq to a crumbling and viciously divided failed state.
Robin Oakley was political editor and columnist for The Times newspaper in London from 1986 to 1992, the BBC's political editor from 1992 to 2000, and CNN's European Political Editor between 2000 and 2008. The opinions expressed in this commentary are solely his.