George Osborne’s visit to China this week is an event of genuine significance. But what is principally significant is not the sight of a chancellor of the exchequer auditioning for the post of prime minister, interesting though that is. What matters much more is that Mr Osborne seems to be using the visit to set out – though without quite admitting it – the essential economic statecraft strategy of the current Conservative government. That strategy, given added immediacy by the higher-than-expected borrowing figures announced today, is to make Britain increasingly dependent upon inward investment by rich, often authoritarian, nations in order to help finance UK economic growth while maintaining a low-tax regime at home.

There are broad echoes of the Gordon Brown era in this. Mr Brown had to face the conundrum of how to supply the Scandinavian levels of public spending the public would like to see while maintaining the American levels of taxation that the public appears willing to pay. His stealthy strategy was to give the UK financial sector its head in return for taxation which he would direct into extra spending on the NHS, the working poor and the elderly. It was a more socially ambitious plan than anything Mr Osborne has admitted to, but both men took as read the political unpopularity that would follow the use of higher direct taxation to finance public goods. Like Mr Osborne, Mr Brown never quite levelled with the public about what he was doing. The strategy was never put to the electorate in a general election. As now, the strategy only became apparent in retrospect, through the chancellor’s actions.

Mr Osborne’s equally stealthy strategic bet is that inward investment, by China and others, will fund large, necessary UK infrastructure projects from which British companies, and hence British workers, will benefit. Other European countries have been equally keen to engage with China for years. But the UK faces dangers that Germany, for example, does not. Germany has a trade surplus with China (though the VW scandal may dent that a little) and a banking surplus too. Britain, by contrast, is running a trade deficit and will now become even more of a debtor country as a result of deals like the one for new UK nuclear power plants that Mr Osborne announced this week.

The reluctance to be explicit about the strategy carries big political and democratic costs. It means that Britain does not discuss the proper limits of Chinese penetration of UK infrastructure, including national energy needs. It means that the British economy is placed in a more dependent relationship with China, at a time when China’s growth is stalling and its stock market faltering. It means that Britain, its foreign policy increasingly in the hands of the Treasury rather than the Foreign Office, has an interest in not challenging Beijing on issues such as human rights. None of these strategies have been seriously debated outside the corridors of Whitehall. They should be, even though the horse has bolted and the stable door is wide open. And the terms of the nuclear power deal should be made public too.

There is something particularly weird about this. In one part of the Tory forest, issues of sovereignty and national destiny are all-consuming. Every twist and turn of the relationship with the EU, including the issue of migration in today’s ministerial meeting, is dominated by the Conservative insistence on the UK’s sovereign right to stand apart. Yet in Mr Osborne’s part of the forest, sovereignty is an almost meaningless concept. China, Russia and the Gulf states can buy up British national assets with the active encouragement of a government that anxiously oils the deals with obliging conditions. In Whitehall, it is hard to know whether there is any such concept as a key national asset. But you can bet your bottom yuan that there is no uncertainty about the concept in Beijing.