Peter Costello fooled everybody and, perhaps in the end, he fooled himself. He was the perfect candidate for the highest office, possessing stature, brains, wit and projection. Yet Costello’s political character fell short of the requirements for the prime ministership in a conundrum that will be debated for many years.

It was one of the main topics of Australia’s national conversation for almost half the post-Cold War era: would John Howard hand the prime ministership to Peter Costello? Or would Costello challenge him for it? From September 1999, when Costello said he had only “another budget or two in me”, to November 2007, when the Liberals lost power, the Howard-Costello leadership tension was a staple of political discussion.

The situation in June 2006 is not unlike that which has played out during the past few weeks. The guessing game of whether Peter Costello would stay in politics or go, whether he would be a leadership candidate or whether he was simply preparing to launch his book, ‘The Costello Memoirs’, and resign, kept sucking oxygen from Brendan Nelson’s leadership. Even after a contracted interview yesterday, there was uncertainty about Mr. Costello’s intentions.

The former treasurer, who retired to the back bench after last year’s election loss, told Fairfax radio this morning he would not retire until he reached the stage where he felt he could not give politics his full devotion. He said there were issues in his Melbourne seat of Higgins that he wanted to address and that he had not made a decision about his future in politics. In addition, Mr. Costello did not rule out standing at the next federal election.

Peter Costello may well leave parliament soon and take a job outside politics. Alternatively, the addiction to politics that has driven him to the heights of federal politics, implementing policies as Treasurer for more than a decade and assailing his Labor opponents for 18 years may yet prevail. For so long as Costello remains on the backbench, it pays to heed history. And history records plenty of future leaders who prematurely write their political obituaries.

In his keenly-awaited memoirs, the former treasurer says he knew “in his bones that the 2007 election was lost even before the first votes were counted - and he blames the loss entirely on John Howard’s reluctance to give him the leadership”. “We lost because we failed to renew,” Mr Costello writes. “We did not arrange the leadership transition.”

There’s no turn-on like genuine lack of interest, as they say, and Peter Costello’s silence this year has proved utterly bewitching. Modern chick-lit is full of advice about what to do when the man of your dreams doesn’t call. Sick with yearning for Costello, some Liberals have resorted to fantasy in recent months. Some journalists, too.

Peter Costello said that he was considering some options outside politics, but would remain in parliament as a back bencher for the time being. “I’ll continue to serve my constituents,” the former treasurer said in an interview. “If I get to the point where I feel I’m no longer able to do that … I’ll make an announcement then.”

According to his own memoirs, Peter Costello thinks he could have won the last election. He says John Howard should have stood aside, let him lead and, because he was younger, and not so reviled, he would have beaten Kevin Rudd. As Costello must in some part of his heart know, this simply isn’t true.

Peter Costello has all but ruled out running for the Liberal leadership. “I’m not seeking the Liberal Party leadership,” the former treasurer said in an interview. “They say: ‘Oh we’ve had a bad week, better bring Costello back.’ I think that’s basically what happened. And I said: ‘No, I’m not seeking the leadership, I don’t want the leadership.’