Garvan Walshe is a former National and International Security Policy Adviser to the Conservative Party. He runs TRD Policy.

If this year has been unusually pell-mell in Westminster, August at least gives us some breathing space. The long-term prospects for our party are not good. The last election saw us lose significant ground, not among the youngest (there wasn’t much ground to lose) but among the 25-44 age group when people normally shed their idealism, start paying taxes, and conclude there’s more to politics than spending other people’s money.

The proximate cause is Brexit, but it’s a mistake to think that Britain’s young have suddenly become passionate admirers of the European idea. They are not tattoing themselves en masse with the 12 gold stars of the European flag. It is Brexitism, the colonel-blimp style ideology not the open and outward-looking “global Britain”, that they detest. They saw the Conservative Party serving up generous helpings of gammon, and recoiled.

The Party has been knocked back to where it was before Cameron “detoxified” it: associated with the old, the white, the rich, and men. Once Brexit is done, this will need to be fixed.

Cameron’s successful strategy for detoxifying the Party to was to seize ownership of an issue on which the Conservatives actually had quite a good record, but were not known for it, and use that to reach out to new, younger voters. For him the issue was the environment. For the next leader (if a challenge to May during the negotiations would surely be madness, asking her to carry on after the negotiations would be cruel and unusual punishment) it should be feminism.

There is a feminist wave breaking, spurred by revulsion at Donald Trump and Harvey Weinstein, and it’s one that the doddery male leaders of Labour and the Liberal Democrats are ill-placed to surf.

The Conservatives, however, are better positioned. When May became leader I remember texting a Labour friend “2 nil, 2 nil, 2 nil”. That is because it is the Conservatives that have had two female prime ministers, not any of the self-described progressive parties. And though it’s true that Margaret Thatcher did not associate herself with the feminist movement in the 1970s, as a pioneer she couldn’t have done so and been able to get to the top (and she obviously disagreed with the socialist dogma that had insinuated itself into much of the feminism of that time). May is different; she put a lot of effort into getting more Tory women into Parliament through Women2Win and has appointed many women to top Cabinet posts. And it should not have gone without notice that the most nationally popular Conservative figure today is a working class lesbian from Glasgow.

But what distinguishes conservative social reform from that of the left is its focus on practicality rather than symbolism. The reason to have more women at the top of the Tory Party is not just to set an example, though example and symbolism are important, but to ensure their perspectives are reflected in the Party’s policy and presentation: their presence in is in many ways a means to an end. It ensures we make policy that reflects women’s concerns and priorities, and appeals to younger voters.

We’re at the cusp of major cultural change, where women — and young men – are unwilling to leave the work of previous generations of feminists unfinished.

The Tory task is to make that change happen in ways consistent with Tory principles and aligned with the way economics and social institutions work, and to prevent it being carried out as part of the heavy hand of Labour Party socialism.

The first became evident to me a few years ago, when I proposed to my students what I thought would be a controversial policy: compulsory and equally shared parental leave, like happens in Norway. I’d expected a debate, with some arguing that it was right for parents to share it half and half, and others advocating more flexibility. Arguments, I thought, would be made on both sides. Instead, there was, a strong consensus in sharing it equally, fully supported by male as well as female students.

The second was during the height of the #MeToo furore over sexual harassment. Not only the usual suspects, but libertarian women, or businesswomen who had dismissed conventional feminism as irrelevant, who hated quotas and all-women shortlists and convoluted debates about gender identity, decided it was time to take a stand.

What links these is, to use a Washington term: people make policy. To get true equality you need enough women with power to decide things in their favour: to make sure women are promoted into positions of power on merit, and not held back by sexist attitudes (even often unconscious sexist attitudes) of their male bosses; and, once there, for them to make sure public policy takes the effects of a historically sexist society on women and the decisions they have to make into account.

This shows up most strongly in the gender pay gap. The issue here is not, or not necessarily, men being paid more than women for the same work (though that accounts for some of it), but of men and women ending up in different jobs, and men being paid better.

The main cause of this is women taking time out of work to take care of children. We can see this by comparing similar families. This gap is about 35 per cent for a woman with a partner but without children; but more than doubles to 77 per cent once she has children.

This has more consequences than just less pay. People paid more usually have jobs that give them higher status, more responsibilty and greater power. The gender pay gap is evidence of a society where women don’t have the opportunities that they should. Worse, that it increases so sharply once couples have children shows that many women are still being forced to make a choice: money, power and responsibility, or a family.

They do so because Britain is particularly bad at helping people pay for childcare. There’s only limited free childcare available, and full-time childcare is ruinously expensive. Employers receive only minimal tax breaks for providing it to their staff, and individuals have to pay for it out of their after-tax income. So when you need to earn an extra £35,000 a year just to pay for it, it’s not surprising that many women take years out of work.

It’s a choice that has had consequences for them, society and the economy. There are millions of British women who aren’t working to their full potential, or exercising positions of leadership. We all lose from their exclusion: from discoveries unmade, businesses unstarted and taxes unpaid. Women working below their potential because childcare isn’t available earn less money, spend less time developing their skills and are less productive than they otherwise would be: behind the gender pay gap is a gender productivity gap.

But it’s a problem within our capacity to solve. The economic benefit of more women working at more senior levels in the economy and of developing their skills instead of taking years out of the labour force far exceeds the cost of providing childcare. Furthermore, because it converts currently unpaid work into economic activity, paid childcare will show up in the national accounts as a boost to GDP — even if had no effect on improving the productivity of women who were no longer priced out of returning to work — and even if funded by borrowing, would not therefore worsen the ratio of debt to GDP.

What remains is to work out the details. It’s a task ideally suited to the new and highly numerate social policy think tank Onward, which is taking up the reforming approach of the early years of Policy Exchange. They have time to work on the detail, so that, after Brexit is done, a reforming Conservative Party can take it up, and start winning back votes of the young lost to the crisis and the last few years of instability.