Chris Patten, the last governor of Hong Kong, perhaps put it best when he labeled the UK’s approach to China as “cakeism”. That is, a vain effort to treat the Chinese Communist Party as a systemic security threat by day and a lucrative business partner by night. To labor the analogy, the UK wants to scoff the cake of easy Chinese investment while keeping the cake of national security. Of course, as anyone who has seriously engaged with the CCP knows, you can’t both eat and keep the cake.

This Janus-faced incoherence has finally collided with reality in the broken slot machine of scandal that is Peter Mandelson, whose lobbying firm, it was reported this weekend, received millions of pounds from a company linked to the Chinese military. While the headlines have understandably focused on the sordid details of his association with the convicted paedophile Jeffrey Epstein, the overlooked scandal lies in what his tenure as ambassador to Washington reveals about Britain’s compromised national security architecture.

Forget vetting. Nobody needed clearance to identify Mandelson’s troubling links to Beijing. Journalists published them. My organization, the Inter-Parliamentary Alliance on China, published them. Long before his predictably ruinous appointment, enough of this was public to disbar the guy from coming within a country mile of the center of power. From his firm Global Counsel serving Chinese state-owned enterprises, to his persistent advocacy for a softer policy on Beijing, to his rampant jollies to the country where he boasted to Epstein of being accorded “God-like status”, Mandelson was never shy about his role as a bridge-builder.

The fact that it took an embarrassing personal connection with Epstein to bring him down, rather than his deeply compromising links to a UK adversary, tells you everything you need to know about Britain’s approach to national security. In Westminster, personal scandal remains the only unforgivable sin, while the systematic erosion of national autonomy through proximity to a hostile state is treated as a mere difference of opinion on policy.

An unwritten story is how influential Mandelson was in steering the UK toward a softer stance on China. As his influence in Keir Starmer’s Labour grew, the party went from a strong frontbench position on Xinjiang and Hong Kong to trying its very best not to talk about Chinese state abuses. He was clever in framing this as a shift towards a more mature and nuanced approach, pushing for an end to the “Tory boycott” of China as if the Conservative government’s outrage at Beijing’s destruction of the Sino-British Joint Declaration was somehow unreasonable.

Let’s be generous. Mandelson’s uncompromising push for closer relations might owe something to a sincerely held view about how the UK can do better in a multipolar world. But it would be naive to dismiss entirely the importance of his own self-interest. When a Government insider, former Cabinet minister and European Union trade commissioner enters the private sector to advise CCP-owned firms, business and foreign influence become inextricably conflated. When that same individual becomes the Prime Minister’s “China whisperer”, it presents a national security problem.

Mandelson has been a vocal proponent of allowing Chinese firms into UK critical infrastructure, despite the obvious risks of dependency and data exfiltration. Some in Whitehall claim he lobbied against the UK imposing tariffs on Chinese electric vehicles. That would be extraordinarily scandalous, if true, given his relationship to the Chinese manufacturing firm BYD. These are not the actions of a disinterested statesman: they are the actions of a remarkably successful example of CCP elite capture.

Yet the problem is bigger than Mandelson alone. The entire debacle stems from a profound conceptual confusion within the British state: what are China’s intentions towards the UK? If Beijing is a systemic threat pursuing a whole-of-state assault on UK society, Mandelson’s ties are a security catastrophe. If Beijing is a golden economic opportunity, then his deep relations are a masterclass in modern statecraft.

By trying to have it both ways, the UK Government created the Mandelson problem. He is an extreme example, perhaps, owing to his once-in-a-generation talent for suppressing scruples, but he will not be the last. National Security Advisor Jonathan Powell, for instance, is a more palatable expression of the same despair. Until Britain ends the incoherence of its China policy and acknowledges that economic engagement cannot be decoupled from national security, it will continue to see its interests traded for the short-term gains of a captured elite.