The former Army officer said he was the only serving intelligence official from the "coalition of the willing" to break ranks before the war started in March 2003.
Time had not diminished the shocking reality that Australia's involvement in the Iraq War was unethical, unnecessary and illegal, he said.
"But no WMD or evidence of co-operation between Iraq and al-Qaeda were ever found," he said in a statement on Monday.
Mr Wilkie said there had been two reviews but no full inquiry into Australia's role.
"The Iraq war will remain a festering sore in Australia's history until a proper inquiry into our country's involvement is held and those responsible for the misadventure held to account," he said.
"Such an inquiry should include the still secret ONA assessments and reports, diplomatic cables and emails which clearly explain the thinking in Washington and London at the time and which make a mockery of the Australian Government's repeated official explanation for the debacle."
Neither Labor nor the coalition have shown any inclination to launch such an inquiry.