The government-appointed panel is due to investigate why the government led by ex-Prime Minister Tony Blair, entered the war alongside then-President of the United States George W. Bush, yet apparently without sufficient preparation for British troops deployed in Iraq.
The Iraq Inquiry into the war, almost seven years later
The five members of the Iraq Inquiry have been drawn from the House of Lords, or Parliament's upper chamber, and will conduct interviews and collect evidence from lawmakers, witnesses, intelligence services, and military personnel over the next year to try and determine the conditions under which the U.K. became intricately involved in the war.
179 British soldiers lost their lives since the war's beginning, and 60 percent of Britons polled believe their country's involvement in the conflict was a mistake, one some say was instigated by Blair's exaggerations of the threat posed by Iraq and its alleged arsenal of weapons of mass destruction.
"Not a court," Inquiry head says; anti-war lobby responds, "not enough"
Inquiry leader Sir John Chilcot has said, however, that the panel does not seek to put anyone on trial for the war. Instead, he said, appropriate criticisms and observations will be made to try and avoid similar mistakes in the future.
Anti-war lobbyists have criticized the panel already, saying it may simply be "a whitewash" of the Blair government's unwavering support and involvement in the conflict. Political commentators said the panel does not promise the war's detractors what they really want - the trial of Tony Blair for war crimes.
"[The public] clamors not for facts but for retribution," said The Guardian political commentator Simon Jenkins.
Calm opening session may heal wounds, observers say
Nevertheless, the panel reportedly opened with a calm and measured discussion of the prelude to war, for which "drumbeats in Washington" began as far back as September 2001, according to William Patey, ex-head of the British Foreign Office's Middle East department.
This sort of approach, some British political commentators and lobbyists say, may be the key to heal the country's wounds, and prevent another unjustified war.