John Le Carré's A Perfect Spy, published in 1986, is sometimes praised as the best novel in the English writer's distinguished oeuvre. The story of the secret agent Magnus Pym, and his meltdown after being trapped by conflicting loyalties, captures something of the ambiguity of anyone who trades in intelligence - or, for that matter, in national loyalty and what sort of purchase it has on people. Who, finally, do such people belong to? Who, in the end, do they serve?

The novel invites readers to think more deeply about what precisely loyalty as a quality is. In what ways can a person's being from a place or part of an organisation mean that allegiance can be demanded of them or a certain mode of behaviour required? Throughout the cold war, many people on either side of the "iron curtain" wrestled with the tensions between ideological and emotional commitment. The more infamous spies followed their ideological bent, largely eschewing whatever emotional pull the country of their birth may have made on them. But even in extreme cases - such as Kim Philby, the most destructively successful of this generation of agents - the accommodations made were never clean or easy. These individuals lived messy, compromised lives as spies, rendered all the more messy and compromised by where they finally placed their allegiances. Lives of such ambiguity are evidently not happy ones, and need to justify themselves by appealing to higher rewards, more remote returns.

A hard calculation

The ambiguities of loyalty, to country or ideology, raise interesting questions when applied to the Communist Party of China (CCP) politicians and members. The party survives, long after that of the Soviet Union imploded, and to a certain extent it has the loyalty of its vast membership. But as the anti-corruption campaign continues to seep deeply into the ultra-elite, lapping at the doors of yet more politburo figures, the character if this loyalty - which kind is good, and which counterfeit or inauthentic - becomes more urgent.

How is it that Zhou Yongkang, now formally charged with corruption, and Ling Jihua, former close aide to ex-president Hu Jintao, and now under investigation, have fallen on the wrong side of the track - while others also associated with vast amounts of reported corruption, such as former premier Wen Jiabao, or even former politburo member Jia Qinglin, have avoided being this fate? Why was Zhou’s corruption the wrong sort? What made it worth the risk of internal instability and fracture to move against him?

At the moment, it's possible only to speculate. Even in an era of new-found transparency, the party's Central Discipline and Inspection Commission (CDIC) is unlikely to put online, Wikileaks-style, the full material incriminating Zhou. If it were to do so, it is unlikely the documents would answer the most fundamental questions. Zhou’s peers, his colleagues, people who, in a collective leadership, made decisions with him and stood by him while he was in power, have now decided that in fact, all along, he was not truly "loyal", was not a faithful servant of the party mission, was, in effect, a traitor and a renegade.

What is revealed here is that ownership of the party mission is the key thing. Somehow, Xi Jinping has been given the authority, or been allowed to claim the authority, to speak of this mission and have a kind of ownership over it. It is now becoming clearer that those that subscribe to Xi's "vision" are regarded as being safe or allies, and that those that are antagonistic towards it need to watch their back.

A complex fidelity

Those seeking to understand China's elite politics are still trying to work out how this process happened - how this "gift" for Xi was arranged. Was it through a long process of design, dating back into the 1990s when he may already have been sighted as a future elite leader; or through enough members of the current political elite, active or retired, realising that so great is the moral crisis for the party that without radically cleaning up its act it might risk falling from power? Is it simply because the party has heeded the lessons of the Soviet Union and understood that if it just becomes a prey to business and commercial interests it will collapse, and that it must redefine its political principles in the 21st century and outline some core beliefs?

Maybe it is a combination of all of these factors. It's tempting to think that the Communist Party of China in the modern era has no beliefs beyond a worship of raw power. But this view doesn’t help explain how and why some in the leadership, like Zhou and Ling, fall foul. Surely the party would then find less public ways of dealing with ill-disciplined members than this unseemly clearing-out? These modern purges indicate something else about what the party as an institution thinks the right and wrong sorts of loyalty are, and what worthy objects of these loyalties might be.

The complex calculation, where fidelity to the party is also fidelity to a vision of China which links the health and fortunes of the two together, is at the heart of the matter. It is a calculation made every hour and every minute of each day in China. Sometimes it is one that leads to individuals being unceremoniously evicted from the party, and sometimes to them being elevated and strengthened, as in the case of Xi.

But if there is one secret formula that observers are always trying to crack about contemporary China, it is this one. Perhaps in 2015, as the era of Xi unfolds, we will come a little closer to working out just how this modern formula about loyalty and faith works, and how it is regarded as delivering a strong party and a strong country in the 21st century. The task of cracking it is unlikely to be easy, however, especially as so many members right at the heart of the party like Zhou and Ling seem to have failed to have made much headway with it. If they had, they wouldn’t now be in such trouble.