The 7 key questions of Chilcot answered

After the attacks on the Twin Towers in New York, George Bush, the US President, vowed to take pre-emptive action against America’s enemies the world over. First he overthrew the Taliban regime in Afghanistan, which was providing sanctuary to Osama bin Laden, the al-Qaeda leader responsible for 9/11. Then Bush turned to Iraq.

Saddam Hussein, the Iraqi dictator, had long been of concern to the US. He invaded Kuwait and was expelled by a coalition, endorsed by the UN and led by Bush’s father, in 1991. The UN then required Saddam to get rid of his chemical and biological weapons, but for 10 years he played cat-and-mouse with UN inspectors.

Tony Blair thought Saddam was a threat to the region and the world, and joined with Bush’s predecessor, Bill Clinton, in a bombing campaign in 1998 to force Saddam to let UN inspectors back into Iraq.

When Bush prepared, towards the end of 2002, to invade Iraq, Blair sought to persuade Parliament that British forces should join the military action.

Because he said that the purpose of the invasion was to get rid of Iraq’s weapons of mass destruction, but, after Saddam was toppled, no such weapons were found.

The BBC alleged that Blair and Alastair Campbell, his communications chief, “probably knew” that a claim about chemical and biological weapons was wrong before they “put it in” the pre-war dossier. This was that Saddam could activate these weapons within “45 minutes”.

After David Kelly, a UN weapons inspector who was the BBC’s source, took his own life, Blair ordered an inquiry headed by Lord Hutton, a judge. Hutton criticised the BBC and exonerated the Government in a report condemned by The Independent as a “whitewash”.

A second inquiry into the intelligence about Iraq’s weapons of mass destruction, by Lord Butler, found that much of it was wrong. The intelligence agencies had assumed Saddam was hiding something, because of his behaviour, so put too much weight on unreliable evidence. Such was the “groupthink” that Blair overstated the spies’ certainty that Saddam had such weapons. Chilcot is likely to repeat Butler’s finding that Blair did not knowingly mislead people.

The situation in Iraq continued to get worse. American soldiers mistreated Iraqi prisoners at Abu Ghraib and, as the country descended into a sectarian civil war, the death toll mounted. In the 13 years since the invasion, about 170,000 civilians have been killed.

Blair was re-elected in 2005 but his successor, Gordon Brown, was keen to distance himself from the war. He promised to pull troops out of Iraq, where they had more or less given up trying to maintain order in the south, for which the British were responsible.

After the last British combat troops were withdrawn in 2009, Brown yielded to the pressure to order a comprehensive inquiry into what now looked like a disastrous foreign policy decision. Sir John Chilcot, a former civil servant, was appointed to chair an inquiry, which was set up not to apportion blame but “to identify the lessons that can be learnt”.

The inquiry panel wanted to provide a complete account and to provide all the documents: this turned out to be a hugely ambitious task. It spent months interviewing witnesses, some of them more than once. It ended up writing, by committee, a vast history of British foreign policy on Iraq from 2001 to 2009.

It meant identifying and declassifying hundreds of confidential documents, including notes from Blair to Bush and transcripts of Blair’s side of their phone conversations. Agreeing what could be published required line-by-line negotiations with civil servants whose job is to preserve the confidentiality of policy discussions.

In addition, one of the panel members, Sir Martin Gilbert, the Churchill historian, died during the inquiry. Finally, the process of Maxwellisation – allowing those people criticised by the report the right to comment on the draft – took another few months.

Not as a result of the Chilcot report. The inquiry was explicitly not a judicial process. Those who think that Blair broke the law hope that the report will provide the information on which a prosecution could be based.

This seems unlikely. The report will look at the arguments about international law, and the Attorney General’s advice that the invasion was lawful, but those are matters of opinion rather than litigation. The International Criminal Court, for instance, has no jurisdiction over the decision to invade Iraq, and no action in the British courts has even been started in 13 years.

Some of Blair’s political opponents in the Scottish National Party and Plaid Cymru have suggested that he should be “impeached”. The word means “charged” and is an obsolete procedure used in the days when Parliament acted as a court, to charge and convict (or acquit) important holders of public office. The last person to be impeached was Viscount Melville, First Lord of the Admiralty, in 1806: he was acquitted.

It would be contrary to natural justice to revive it now, and in any case Blair no longer holds public office.

It is not going to satisfy the more virulent critics of the Iraq war, because it will accept that Blair acted in good faith. However, it will probably say that the decision to join the American invasion was a bad one.

The report will be an important exercise in open government, publishing almost everything so that people can make up their own minds. But the “lessons that can be learnt” have been pretty obvious for some time. Indeed Colin Powell, Bush’s Secretary of State, warned President Bush beforehand: “You are going to be the proud owner of 25 million people. You will own all their hopes, aspirations, and problems. You’ll own it all.”

However justified military intervention might seem, and in this case it was arguable, you have to have a plan for what comes next.