John Gorton, who was prime minister from 1968 to 1971, was a true believer in nuclear. His biographer Ian Hancock wrote that Gorton "visualised the generation of cheap electricity, and fuel for transport of all kinds".

Gorton declared in his policy speech for the 1969 election:

"We shall, during the next parliament, take Australia into the atomic age by beginning the construction of an atomic plant at Jervis Bay [on the NSW south coast], to generate electricity. We believe that Australia will make increasing use of atomic power in the years ahead and that the time for this nation to enter the atomic age has now arrived."

Plans were well underway when in 1971 Gorton lost the prime ministership to Billy McMahon, a critic of the Jervis Bay project, which was put into limbo. Treasury did an evaluation that - you've guessed it - slammed the cost; a journalist at the time described it as "a most devastating critique". The way was opened for coal, which was much more economically viable for Australia's power generation. The Jervis Bay project was dead.

Peter Dutton is a very different brand of Liberal from the freewheeling, often undisciplined Gorton, but he has become as convinced as his predecessor about the nuclear path. And, just as in Gorton's time, the critics cite cost. Only now the cost issue is about renewables versus nuclear.

Dutton, under pressure to release policy, says the opposition will put out its nuclear energy blueprint before the budget.

It seems an odd choice as the year's first big policy hit - nuclear power isn't dominating kitchen table discussions around the country. Leaving that aside, the release will be a major test for Dutton, in handling both the economics and the politics of the ensuing debate.

He starts with most energy experts ranged against him. He's obviously not himself an expert, so being convincing when he has to get into the fine detail won't be easy. Public attitudes towards nuclear may have softened, but if he flounders in defending the economic case, he'll have lost the argument even before the politics kick in.

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One aspect of the evolution of the opposition's nuclear policy that raises an eyebrow is how it has so quickly transitioned from concentrating on small modular reactors - which spokesman Ted O'Brien spruiked enthusiastically but most experts dismissed as impractical - to being centred on conventional reactors. It might have been a sensible move, but it makes you wonder whether the policy crafters were on top of the complexities to start with.

The political battle over nuclear will be on several fronts: the overall scare campaign, the regional reaction, and attitudes in the cities.

The opposition hopes its plan to place the reactors (about half a dozen) only on or near the sites of coal-fired power stations as they phase out will limit the effectiveness of Labor's scare assault. It will then become a matter of persuading the affected local communities, and Dutton has flagged incentives.

More generally, the opposition aims to persuade regional voters that nuclear is better than having their areas covered with power lines and wind farms that many find ugly and intrusive. This would probably resonate in many areas, provided Dutton could allay other doubts with these voters, such as about cost.

The cities will be another matter. In teal and similar seats, a strong commitment to renewables is likely to make voters unsympathetic to the nuclear case. The opposition may not have great hopes of winning back the teal electorates, but it will be aware of the risk of losing more seats to teal candidates and so it has to be careful.

In outer suburbia, Dutton's target territory, the danger for him is that voters see nuclear power as a side issue. Yes, they will hear his claim it would mean lower power prices but, even if they buy that very contested argument, they'll know that would be far into the future.

Hard-pressed families are interested in the here and now. And that goes to a broader problem for Dutton's nuclear campaign. It could lead up a dry gully, a debate that consumes time and effort better spent on more central cost-of-living and other issues.

Dutton says the opposition won't be a small target at the election. Even if that's sound thinking, he needs to have reasonable confidence that "big target" policies will carry a more than fifty-fifty chance of paying significant dividends. He doesn't have much political capital to spend. The likely dividend from the nuclear policy could easily be a net negative.

Dutton might be a nuclear believer but his stand also has to be understood in a Coalition context. His most important priority since the election has been keeping unity in the opposition's ranks. He has managed this but it is always potentially precarious.

The Nationals have been bugbears for Liberal leaders on energy policy. Currently the party is divided between those who support the 2050 net zero emissions target (including leader David Littleproud) and the radical outliers who'd like to ditch the commitment to the target, which the party only signed up to under duress in the runup to the last election. The radicals would also like to ditch Littleproud if they got a chance; there are conflicting assessments about how stable his leadership is.

For multiple and obvious reasons, Dutton can't afford to see the Nationals fragment over the 2050 target, or have his conservative Liberals arc up about it. The nuclear policy is the glue keeping various bits of the Coalition stuck to the target. Dutton argues the opposition believes in renewables but they won't alone get Australia to the target. "Labor sees nuclear power as a competitor to renewables," he said this week. "We see nuclear power as a companion to renewables." It's an energy policy that gives something to various otherwise irreconcilable groups within the Coalition.

The nuclear pitch will come under scrutiny when in May the CSIRO releases its GenCost report, titled Annual insights into the cost of future electricity generation in Australia. The result of its examination of nuclear could be a serious blow for Dutton. If so, seen in historical terms, that would be a win for McMahon economics over Gortonian aspiration.