The winner of this Tory leadership race will be the spirit of Thatcherism

Along with making tortured comparisons with Game of Thrones, the laziest thing to say about the Tory leadership contest is that it is going to be all about Brexit. That much is obvious, given Theresa May’s abject failure on Europe. The bewildering number of candidates will of course have to spend the next few weeks explaining how they’ll make a success of Brexit in her place.

A purity contest is well under way, as candidates try to demonstrate they are the most Brexity of them all. If you voted for May’s Brexit deal, or failed to resign after the Chequers agreement, then you’ve got a lot of explaining to do.

Boris Johnson, Dominic Raab and Michael Gove are all on different parts of this spectrum, and their supporters are already pointing out which of their rivals is the most tainted by association with May’s hated deal.

Related: Dominic Raab defends calling feminists ‘obnoxious bigots’

On the other hand, if you’re a remainer like Philip Hammond, then you’re threatening to force out the next prime minister if they go for a no-deal Brexit. Some candidates want to appeal to this wing of the party by saying that they are more pragmatic than other colleagues, and have the negotiating skills to get a better deal. Few are being honest about the realities of the parliamentary arithmetic and the likelihood of the European Union reopening the withdrawal agreement.

But to focus solely on Brexit would be as hackneyed as thinking that Game of Thrones is the only cultural reference people can understand these days (which is particularly odd given how convoluted the plot is). There is a big dimension of this contest that is about the sort of Conservatism the party wants to espouse. Theresa May failed to produce a successful and coherent domestic policy. The changes that she tried to make cast the Tories as a rather paternalistic, interventionist Christian Democrat-style party. After the catastrophe of the 2017 manifesto and May’s inability to achieve very much at all on the domestic front before or since, many Tory MPs on the Thatcherite, free-market wing of the party are determined to put their way of thinking back in power.

Some of the most powerful Thatcherites aren’t standing but will make their presence felt. Liz Truss – who has built an extraordinary media profile that combines the ridiculing of ministerial colleagues who are expanding the state with a declaration of love for cold pizza – has ruled herself out but is clearly an important agitator in the contest. Others look unlikely to win but will act as tugboats, pulling the narrative to the right: Steve Baker, who is more Christian Libertarian than Christian Democrat, is one such who wants his party to focus on freedom and flatter institutions. Dominic Raab, currently one of the favourites for the final two, co-wrote a manifesto for change in 2012 with Truss and other free-enterprise Conservatives. Raab kicked off his leadership campaign on the Andrew Marr Show by promising to cut 5p from the basic rate of income tax. This, in classic “shrink-the-state” fashion, would be funded by cutting the number of government departments and chasing greater public sector efficiencies.

The book he and Truss helped write, Britannia Unchained – or Britannia Unhinged, as this newspaper described it – was a plea for the Conservative party to open up public services to market forces, to reduce the size of the state and better support innovation. Another co-author was Priti Patel, who is yet to declare. She recently said that her party was consumed by a fight between “those who believe our purpose is to be more prescriptive and controlling; and those who believe that our party – the greatest and most successful political party in the western world – should promote the cause of freedom and liberty”. She called the first approach a route to “soulless managerial decline”.

Brexit then could yet become the vehicle for Thatcherism redux as the Conservative party returns to the uncompromising economic liberalism that changed our political weather in the 1980s. Even contenders who think a Brexit deal is in the country’s best interests and who worry about bringing the party back together are aware that neither the majority of MPs nor the grassroots are in the mood for a consensus politician. All plan to avoid using the C-word, compromise, in public as they believe May’s emphasis on it in her final weeks has made it too toxic.

The MPs most willing to compromise are those on the “moderate”, largely pro-remain wing of the party. They know they’re most likely to get a Brexiter in charge, but are interested in whether that new leader is also a One Nation Tory, or a dry economic liberal who they fear will cut the state back even more. “We all say we are Conservatives and want to lower taxes,” says one MP. “But in reality a lot of us are looking at what’s going on in education and local government and know that we cannot cut taxes any more, and in fact we need to find ways to get spending up so these areas can function.”

Related: Tory leadership race: the favourites to replace May

These MPs see Raab as the greatest risk to the party because he believes in a much smaller state than they can stomach. And that’s why many of them are contemplating backing Boris Johnson, or at least not launching the kind of attacks on him that the Gove camp have already started. They see the former London mayor as the sort of political chameleon that they can work with, someone who endorsed a higher minimum wage and who doesn’t stick rigidly to one set of political beliefs. Some of these MPs privately loathe Johnson, but think he may be the most likely contender to carry out their work while keeping the right of the party happy.

The problem with Johnson is that he hasn’t yet offered any evidence that he’s capable of achieving much in high office. His campaign team don’t plan to spend much time talking about his tenure as foreign secretary, which is wise given how casually he treated that job. But already Michael Gove is arguing that, unlike candidates such as Johnson, he has the ability to deliver Brexit. Given May was so spectacularly bad at tackling the “burning injustices” she claimed to be horrified by, Tory MPs will be interested in competence in this election, too. One Nation Tories should beware assuming that just because Johnson believes in many of the things they hold dear, he has a good chance of delivering any of them.

Johnson and May couldn’t be more different in personality, but they might both share the same flaw of not being able to get as much done as they believed they were capable of. May’s failure was because she was meddling and indecisive. Johnson’s would be down to a lack of attention to detail. Politicians are supposed to campaign in poetry and govern in prose. But if the Tories end up electing a second leader who produces merely nonsense verse, then the ensuing chaos will make those comparisons to even the bloodiest scenes in Game of Thrones look even dafter than they already are.

• Isabel Hardman is assistant editor of the Spectator and presenter of Radio 4’s Week in Westminster