Abbott rightly points out in that book that we rarely know in advance what a new government will be like. Few in 1975 would have expected the Fraser government to keep as much of Whitlam's legacy as it did; few in 1983 would have tipped the Hawke government to become the path breaker for micro-economic reform. He might have added that few anticipated the global economic slumps that helped undermine the Whitlam and Rudd/Gillard governments.

But Battlelines (soon to reappear in a new edition), and Abbott's years as Opposition Leader, provide strong leads on how he might tackle the challenges he would face as PM.

Like John Howard, Abbott is a mixture of tribal ideologue and political pragmatist. Howard's success came from his remarkable ability to balance the two. As I wrote in 2005, he was ''a man of extraordinary self-discipline and patience, who listens to critics, weighs up arguments carefully, and judges shrewdly how far he can push things''. His tribe was small business, but part of him was the tracksuit-wearing patriot who wanted to be (and was) prime minister for all of us.

Abbott is different. His tribe is a smaller one: affluent Catholic traditionalists. Since student days, he has defined himself more by what he is against than by what he is for. He is for the monarchy, and the church, and traditional values, but he decided long ago not to tie his political career to them. Howard once called him an ''arch-pragmatist'', and he is. Rule one for an Abbott government will be: do no harm to his chances of winning the next election.

Where Howard and Abbott also differ, however, is that, as yet, Abbott has shown no desire to be a leader for all of us. If he had that instinct, he would have handled the superannuation and public transport issues differently. With one important exception - indigenous Australians - he has shown no empathy with the groups Labor and the Greens represent. If they propose doing something, such as tackling global warming, his natural instinct is to oppose it.