The incomplete Greek elections also raised the question of what happens when an election result points towards reneging on a previous agreement. In this case it was the previous Greek government's agreement to austere bail-out measures imposed on them by the rest of Europe. In Germany too, Angela Merkel's party has recently lost a big state election on the anti-bailout issue.

At one level there can be no argument. Election results in a democracy cannot be questioned. New governments that make clear their proposed policies during an election campaign have every right, indeed a duty, to introduce their promised policies no matter how radical they are and no matter how much they are a complete reversal of the existing situation. They have a mandate.

At another level, though, there are restrictions on incoming governments. The constitution is one restriction on what they can lawfully do, supported by the separation of powers between the legislature and the judiciary. The High Court has a role. Contractual arrangements with commercial interests are another limitation, as are treaties signed with other nations. In bicameral parliaments there is also the question of whether the new government can successfully put its new measures through the parliament. So new governments, no matter how decisive their victory, may have to tread carefully.

The debate in Europe goes something like this. Hollande promised to withdraw all 3300 French troops from Afghanistan. But allies and commentators have questioned the move despite the election result. The Spanish Defence Minister reckoned that ''the responsibility of France in the Afghan commitment is above personal opinion''.

A Harvard University professor explained what this might mean when he commented that ''In international politics, you don't just commit a presidency, you don't commit a political party, you commit a country. Those are commitments that France undertook''. Both comments seem to imply that there are some things that are beyond democratic change at an election.

What will happen in Greece at the second election is unclear. But what is clear is that the mood, led by the leftist Syriza Party, is for renouncing the loan agreement that the out-going Greek government signed last February. Many Greeks, perhaps a majority have had enough of austerity.

The relevance to Australia is that the likely government after the next election has made clear that it will make drastic changes, though they will not include foreign policy where there appears to be bipartisanship. The Opposition has signalled a complete change of direction. The changes include removal of the carbon and mining taxes, finding large budget savings, and, to the extent possible, reshaping of the National Broadband Network. Big changes will also be made to refugee and asylum seeker policy. This is likely to be one of those elections where an awful lot is at stake.

The Opposition, which in government may have a mandate supported by a decisive election victory, will brook no opposition or compromise. They say that they will insist on their mandate and as a consequence they will take the nation to a double-dissolution election if they are resisted by the Senate. Undoubtedly they also hope for an early election so that certain Gillard government tax policies are not given time to settle in.

By contrast that is just what the government is trying to do. Dreadfully unpopular, it is trying to dig in and buy time. It wants to embed its policies so that their merits become recognised by voters and so that they are more difficult to change. Implementing policies takes time. That is why one-term governments are deemed failures. It is not just that they have proved themselves unpopular, but that one term is not enough to embed new policies. As a consequence, the incoming government can easily get rid of policies that are seen to be discredited.

The Rudd-Gillard Labor government is caught mid-way between being a one or a two-term government. It is sort of a one-and-a-half term government at the moment. It must reach the second half of 2013 to be recognised and respected as a fully-fledged two-term government (beginning in November 2007).

Political history in Australia shows that alternating democratically between one party and another in a two-party system leads to a mix between continuity and change. There was actually a lot of continuity between the Whitlam and Fraser years despite the bitterness of the 1975 constitutional crisis. Kevin Rudd promised a fair bit of continuity when he challenged John Howard in 2007.

But sometimes the emphasis is on change, as it was when Howard defeated Keating in 1996. On the face of it, at both the international and domestic levels, we are now in a period of potential dramatic change at election time. There are many differences between contemporary European and Australian politics. But the recent French and Greek election experience offers food for thought about the issues involved in drastic change with an election mandate.

Dramatic change is not easy to achieve. There are pressures behind the status quo and limitations on what new governments can do. Rolling back existing policies is never easy because expectations have been built up, even when the outgoing government is unpopular. A clear-cut election mandate often ends in compromise policies for a mixture of good reasons.

John Warhurst is an emeritus professor of political science at the Australian National University. John.Warhurst@anu.edu.au