It might be hard to take the future of the Conservative party seriously right now – but we must | Martin Kettle

The contest to succeed Rishi Sunak as Conservative leader may seem like an argument between corpses in a tomb. The candidates are yesterday’s rejects. Not even the hysterical headline-writers of the Tory press can bring themselves to hype the race as they would in the triumphalist years. The infantile tabloid screams of “Boris this” or “Suella that” seem to have gone quiet, though probably only briefly.

After the babel of those years, a period of relative Tory silence will be welcome to many. But the future of the Conservative party is a genuinely important matter – not just to Tories themselves, but also to the workings of parliamentary democracy and to the dynamics of British politics. The election to succeed Sunak, the preliminaries of which began this week , should not be scorned as an irrelevant event.

Conservative MPs describe the post-election mood among their drastically reduced numbers as sober and serious – as well it might be. On 4 July, remember, the party did not merely lose power. It suffered the worst electoral drubbing in its long and frequently victorious history. After 14 years in government, peaking with the 80-MP majority of 2019, the Tory party was reduced overnight to 121 MPs and 24% of the vote, trailing in every single region of supposedly Tory England , and with no MPs at all in Wales.

Sober and serious are, therefore, fully justified words in these circumstances. Indeed, it would be bizarre for Conservatives to adopt any other view. Theirs is now a party adrift in an unfamiliar land. Whether the MPs’ sobriety is shared by the party’s defeated candidates, its local councillors and activists, or its grassroots membership, is less certain. At Westminster, however, the gravity of the party’s defeat is instantly palpable.

You could see this during Keir Starmer’s prime ministerial debut at PMQs . From the opposition benches, Sunak was self-deprecating and chastened, and the Tory MPs behind and around him respectful and on good behaviour. Significantly, Sunak asked all his questions about support for Ukraine, a stance which not only allowed him to appear bipartisan with Labour, but also to draw a clear dividing line against the sometime Putin apologists Reform UK and Donald Trump.

As so often, Sunak is a reflection of a Tory mood, never its driver. His inability to tame the pre-election Tory party that he inherited from Boris Johnson and Liz Truss was repeatedly exposed as prime minister. Since the election, this has segued into an inability to give a clear direction to the party now that it has been catapulted into opposition. It is his biggest limitation as a politician.

When he announced his resignation outside No 10 on 5 July, the former prime minister privately favoured a quick campaign to choose his successor. That has not happened. Under the rules announced this week , Sunak will remain leader until his replacement is announced on 2 November. His 121-day stint as opposition leader will be the longest by a defeated prime minister since James Callaghan stayed on for 17 months after Labour was defeated in 1979.

The Conservatives have rolled the pitch for what may be a different kind of leadership battle to those that were won by Johnson and Truss. New and more complex rules have quietly been introduced. Candidates must be nominated by next Monday. They will then set out their stalls before MPs whittle the field down to four, if that is necessary, in September. Those four will make their cases at the party conference in Birmingham at the start of October. Back at Westminster, Tory MPs will then reduce the field to the final two, before the members make the final choice, with the ballot closing on 31 October.

These are certainly not root-and-branch changes to the membership-dominated election system brought in by William Hague. That issue has again been ducked. The members still get to make the final call, a power which they used to give the party Johnson and Truss, though also David Cameron about 15 years earlier. But some of the hurdles have been rearranged, and MPs will have more opportunities to shape the run-off. The party conference will be crucial, though the expense of attending means that many members will not be paying the kind of attention that the media will.

This is nevertheless a limited victory for those who have argued that the party needs time to think and to make serious choices. Given its divisions over so many issues, this would appear an unavoidable part of any reconstruction process. But will that window for self-reflection – in effect the months of August and September – be used, especially by Sunak and by those who want to take over?

It is hard not to be sceptical. There is much discussion taking place on social media and on Tory blogs, some of it highly thoughtful. But it is rare for leadership contenders in any party to pose uncomfortable questions. Modern MPs have to watch their backs more than those of earlier eras. The platonic ideal of an informed internal debate will not happen. But the facts of 4 July and what led to it can hardly be ignored either.

Related: The Conservative party faces an onerous task to rebuild itself, and every Tory must have a say | Tobias Ellwood

There are three things, in particular, that the Tory party must somehow face. One, highlighted by the psephologist Lewis Baston, is that the Conservatives lack a coherent centre-right project of political economy that attracts enough voters. They have abandoned new generations of aspirational voters with generally liberal values while flirting with Reform UK and its effort to build what Baston calls “an anti-rainbow coalition”. The new leader must choose a different path. This is fundamental.

Another factor, trenchantly argued by the centre-right blogger John Oxley, is that the next leader must see party rebuilding as “the only way back”. Tory grassroots members may shape the party in some ways, but numbers have collapsed and organisation has been neglected. As Oxley puts it: “It is almost a sideshow to argue whether the party has been too left or right, wet or dry, conservative or liberal … The party failed because it has been too crap at campaigning, communicating and governing … The real work lies in rebuilding its capacity to all of those and aligning with a group of voters who want to support it.”

The final point is that it matters. Severely weakened though they are since 4 July, the Conservatives are still easily the second party in the land. One day, Britain will again need to have an alternative government, or a government in waiting. You may understandably not support the Conservatives, and you may also want Keir Starmer’s new government to prosper and govern well for a generation. In the end, though, it is far better that what comes afterwards should be in the mainstream centre-right tradition, if that can be reconstructed, than from the populist right – or worse. Like it or not, you too have a dog in this fight.

• Martin Kettle is a Guardian columnist