To avoid this outcome one or both of the main parties needs to be completely reinvigorated. That will require an entirely new model of party, in which members are recruited online, can choose their level of commitment and are incentivised to recruit others. In terms of communication, using the internet and direct mail, the membership model of organisations such as the 4 million-strong National Trust has a lot to teach the parties. But in the case of the Conservatives, genuine power should be devolved to the grassroots. Members used to having choice in many other aspects of their lives are hardly going to sign up any longer for blind loyalty.

It is also worth thinking about those millions of recent immigrants, even if your contention is that the flow should be slowed or the door closed. Those who are here are mostly here to stay. They are having children, putting down roots and in many cases paying taxes. Eventually, they may even be persuaded to vote in large numbers. If the Conservative party in particular is serious about saving itself then its leadership will have to be nimble. It must find an optimism-drenched way of winning back the party's traditional supporters it has dismissed, while reaching out to new aspirational voters and persuading them that the Tory party stands for work, community, responsibility and the nation. That could be a winning combination.