The former top commander, who chaired the defense staff between 1997 and 2001, said the then US Defense Secretary Donald Rumsfeld has a “lot to answer” over allowing the Iraqi army to be taken apart, rather than removing its top commanders and clasping “the army to their bosom”.
This comes as Guthrie also pointed the finger of blame at the then Prime Minister Tony Blair for going to the war along with the US without adequate justification.
The top commander’s views were backed by other senior military figures including Air Chief Marshal Sir Brian Burridge, ex-Army chief General Mike Jackson, chief of the defense staff at the time of the invasion Lord Boyce and Lord Dannatt, Jackson’s successor.
The commanders all stressed the fact that the war lacked a “proper” planning with the US making things worse by “totally disbanding the Iraqi army and the Ba'ath party, the two instruments of the Iraqi state that could have exercised some control", as Dannatt put it.
The result they said was an “enormous vacuum” that created a security chaos in Iraq.
"It was a national disgrace that, having flown over much of the country for 13 years, you could have not done better in building up a proper intelligence picture," Burridge added.
He also said that Blair had a burning enthusiasm for “solidarity with the US”.
This comes as former Cabinet Secretary Lord Wilson had also told the Chilcot Inquiry into the Iraq war that Blair had an appetite for military intervention.
"There is a gleam in his eye that worries me,” he said.
All of the commanders have already given evidence to the Chilcot Inquiry that will report on the legality of the invasion of Iraq and Britain’s participation in the conflict later this year.
The Iraq war turned into a headache for the British government only months after the invasion, with talks of Blair misleading the MPs to go to war, raising questions about its very legality.
Lord Goldsmith, Tony Blair's top legal advisor and attorney general at the time of the 2003 invasion, told the Iraq War Inquiry (Chilcot Inquiry) in January 2011 that Blair hoodwinked the MPs by claiming that Britain could legally attack Iraq even without a United Nation's approval.
Goldsmith also told the inquiry that the former Labor PM told the MPs in a statement on 15 January 2003 that there were “circumstances” in which an attack could be legal without UN approval.
A former chief of the British Defense Staff General Charles Guthrie says Britain was led into the war in Iraq in a “wholly irresponsible” way.
"It was absolutely irresponsible to go in without thinking of the consequences," Guthrie told