This was the man who, for nearly a dozen years, represented Australia in the high councils of the world. As this anecdote reveals, Downer can be petty and puerile. He plays a mean-spirited, personal, scratchy game of partisan politics. He can be breathtakingly immature.

He was always ready to be flippant and frivolous. He was something of an Inspector Clouseau of foreign ministers: pompous, slightly ridiculous, self-important, hard to take seriously, though ultimately getting through most of his assignments with some bare seat-of-the-pants competence.

Flippancy can be entertaining but, when employed injudiciously by a foreign minister, can compromise Australia's interests. Downer shared the podium with the New Zealand Trade Minister, Phil Goff, at a dinner a couple of years ago as part of the annual Australia-New Zealand Leadership Forum. This is a quasi-official initiative which holds its events off the record.

The big complaint against Australia at the time, and perennially, was about Australia's ban on NZ apples. Canberra says NZ apples cannot be imported because they may infect the Australia crop with the disease fire blight; Wellington argues this is a pseudo-scientific cover story for naked protectionism.

When Downer took the microphone, other diners recollected, he said: "I just want you all to know that all Australian quarantine decisions are science-based" - pause - "it's called political science."

As these anecdotes illustrate, Downer never learnt the lesson of his tenure as a failed leader of the opposition. His leadership of the Liberal Party was already in strife but it was his ill-judged joke about domestic violence - "the things that batter," Downer chortled - that brought his term to a rapid end. He remains the only Liberal leader who never got to contest an election. Downer lacked judgment, and that lack of judgment meant he never acquired gravitas. He held high office, but at a low level.

"He holds the record for the most unpopular opposition leader in 36 years," the life of Australia's longest-running political poll, the Nielsen poll, according to Nielsen's John Stirton. Even his mother couldn't pretend he was any kind of a success as Liberal leader: "It wasn't easy - of course it wasn't," Lady Downer told the journalist Annabel Crabb some years ago. "But he didn't do very well, so one must face up to that."

Paradoxically, it was Downer's short and disastrous tenure as opposition leader that created the conditions for him to become Australia's longest-serving foreign minister.

By agreeing to a peaceful handover of the leadership to John Howard, Downer allowed Howard to take the job bloodlessly. Howard was indebted to Downer. He repaid the debt by allowing Downer the portfolio of his choice - foreign affairs - and allowing him to remain in it as long as he wished.

A prime minister would have removed a minister with a first year as bad as Downer's as foreign minister. But, because of his debt, Howard supported him unswervingly.

Perhaps Downer's greatest political failure, however, was not his inglorious term as Liberal leader but his time as foreign minister. Because it was while Downer was minister that his shadow minister, Labor's up-and-coming Kevin Rudd, made his running as the inevitable new leader of the Labor Party.

Rudd came to win the respect and confidence of the voting public in the years he was facing off against Downer. The foreign minister was unable to derail or discredit Rudd. Instead, he was the perfect foil.

It was while Rudd was prosecuting the attack on the AWB scandal, the Iraq war, the "Pacific solution" and the failure to sign the Kyoto Protocol that he demonstrated his competence and soundness. It was this performance that persuaded the voting public, and then the Labor caucus, that Rudd was leadership material. In this sense, Downer helped create the leader who destroyed the Howard government.

As he announced his retirement from Parliament yesterday, Downer said his greatest accomplishment was to bring freedom to the people of East Timor. And it was a signal achievement for Australia to act as midwife at the birth of an independent East Timor.