Whom the gods would destroy, they first make mad, according to Euripides. And Lord Owen would agree. His new book blames the fiasco in Iraq on psychological failings in George Bush and Tony Blair - failings Owen dubs "the hubris syndrome".
Leaders suffering from hubris are usually emboldened by early successes, Owen explains - in Blair's case, the intervention in Kosovo. They start to believe themselves capable of anything. "This excessive self-confidence leads them into misinterpreting the reality around them and into making mistakes. Eventually," he writes, "they get their comeuppance and meet their nemesis, which destroys them."
It took the neurologist and peer a while to spot the symptoms in Tony Blair. Indeed, he backed the invasion himself, wanting Saddam gone, and succumbed to the ex-PM's blandishments when he was looking for backing. His wrath, one senses, comes partly from outrage at the suffering inflicted on the Iraqi people, partly from injured pride and partly from frustration that the tragedy of the invasion has not yet played itself out. He believes the protagonists should have fallen on their swords by now.
"I could see what he [Blair] was trying to do, I thought his motives were honorable. But it had failed. He no longer had the trust of people like myself," he says, sitting in the Limehouse flat just yards from where the Gang of Four broke away from Labour to form the SDP in 1981.
His critics would say that Owen is used to disillusionment and rupture, never mind hubris. The crossbencher resigned twice from the Labour shadow cabinet, broke with the party itself, then quit the SDP when it merged with the Liberals. But Owen says his attitude towards Iraq has been perfectly consistent. "The story of Saddam Hussein and my involvement with him goes back a long way. I've watched him pretty carefully ever since I was told that this Iraqi former PM had been assassinated on the streets of London in the summer of 1978." He was foreign secretary at the time.
"No one had any doubt [Saddam] had authorised that assassination ... I was very unhappy about a lot of our policies in the 1980s. I thought that we got Saddam Hussein quite wrong, and I was particularly upset when he was known to have used gas."
He believes Britain wrongly stood by during the Iran-Iraq war in the vain hope that the Islamic revolution would burn itself out. So surely he wishes General Schwarzkopf had removed Saddam during the first Gulf war?
No, he says. "We were bound by the UN resolution, which was to get him out of Kuwait, and if we'd gone on to Baghdad we would have broken the quite extraordinary coalition that Bush senior had involved ... But I was passionately in favour of doing something to help the Kurds."
He takes some of the credit for persuading John Major to establish the no-fly zone. "One thing you could not possibly do in a humanitarian mess, with all these Kurds being pushed up to the mountain areas, was to go on allowing them to fly helicopters." But Owen gradually lost confidence in the UN's ability to coordinate a humanitarian operation, enforce sanctions or find WMD.
"There was real concern that Saddam was getting better ground-to-air missiles and that fairly soon we would have found it quite difficult to avoid having our planes shot down." So he was perfectly ready to believe Iraq was developing WMD. In any case, he says he supported regime change for its own sake and wishes Blair had made the case for it.
Read the UN charter properly, he claims, and you can find plenty of justification for pre-emptive invasion, provided the regime is a threat to the peace. One of the big mistakes Blair made, he believes, was to inflate reports of WMD instead of arguing for regime change. The other great error was not to have a better post-invasion plan. He met Blair a few times during this period: didn't he spot these oversights?
"Perhaps I could have picked it up. But, you see, most of my normal contacts in the diplomatic service were literally cut out of this process, so you wouldn't have got it on the civil service gossip vine. There were very few people involved - all in No 10 - who actually knew the real score about what was happening."
He did lend Blair Jonathan C Randal's After Such Knowledge, What Forgiveness?, a book about the betrayal of the Kurds by the west. "But it was clear to me even six weeks later he hadn't read the book. Now, I suppose prime ministers have got a lot of other things to do. But I'd given it, actually, to Jonathan Powell, his chief of staff, and said, 'No doubt Jonathan might read it and warn you of some of these things'." Six weeks later, it was clear he had not.
Has Blair realised the scale of his mistakes? "I don't know," Owen replies. "I remember meeting him in the winter of 2003, and even then he was a chastened person." Really? Blair felt guilty? "I genuinely hope so ... it was never obvious." He is also annoyed with Blair for allegedly negotiating his new job as Middle East envoy during the last EU summit and coming up with an "absolutely duddish deal" on the European constitution. Still, "I wish him well. These jobs are pretty thankless. I did it for nearly three years in Yugoslavia."
Right now, he wants another inquiry into the run-up to the invasion. "I am a doctor in part, and doctors learn from postmortems. One of the things I've always been angry about in politicians is their failure to go back over their mistakes, and their reluctance to learn from them."
I put it to him that voters seem to be attracted to hubristic personality types who are liable to lead them into risky foreign ventures. Given Owen's own failure to spot the disease before the invasion, how can we hope to stop such people achieving power?
"You put your finger on a very deep issue, and also one that concerns me personally," says Owen, with all the suavity of which he is capable. "I say in the book that at one stage I was attacked for being megalomaniac by a friend of mine - a journalist - and I'm sure other people at times thought it." (According to Denis Healey, another of the Gang of Four, Roy Jenkins once compared Owen to "the fabulous Upas tree which destroys all life for miles around it.")
"People want people who are capable of taking courageous decisions ... But that does render you more liable to the charges of megalomania, it does render you open to the possibility of this hubris syndrome. So I do think there is pathology undermining the hubris syndrome. That doesn't mean you can't hold them accountable and that they shouldn't resign, but at least you can understand what happened to them."
At times the book reads like a psychologist's report, at others, like an indictment of arrogant government and failed diplomacy. Owen's detractors will chuckle bleakly at the title and probably mutter "Physician, heal thyself". But, reading it, one senses that Owen - always irresistibly tempted by power, always disappointed by the failure of others to follow his advice - is aware of his own potential to suffer for hubristic behaviour. Not, of course, that he would ever let it emerge.
· The Hubris Syndrome is published by Politico's, priced £8.99
