When considering the latest outbreak of persecution against Christians in China, what you have to understand is that there are already thought to be more Christians there (some 100 million) than members of the Communist party (87 million). This is not an impressive outcome for 70 years of intermittently ferocious atheist suppression of religion: when the Communists seized power in 1947, there were only around 4 million Christians in the country. Under Mao, an estimated 500,000 Christians died for – or because of – their faith. Yet since the Maoist state was opened to capitalism in the 1980s, Christianity, along with other religions, has grown at an astonishing rate.

This week it was reported that Christian leaders in eastern China had taken to the streets in protest at the removal of crosses; in the past two years, it’s estimated that more than 1,200 crosses have been removed from churches in Zhejiang province as part of a government initiative. The periodic campaigns against Christianity in China might suggest that the religion is a foreign import that the authorities can hope to suppress, and a fringe element in Chinese life. This would be almost entirely wrong. Although Christianity is undoubtedly an import to China, Christians argue that it is as well placed as any religion there, since the Communist regime so successfully persecuted traditional Chinese belief systems as well.

China is on course, over the next 15 years, to become the world’s most populous Christian nation. It is also home to the largest population of atheists in the world – according to Pew Research, 46% of the world’s atheists are based in China. There are Muslims in the west of China and Buddhists in Tibet, for both of whom religion is also an expression of national or ethnic dissatisfaction with the Han Chinese. Traditional religion is also returning. But there’s no doubt that Christianity is growing the fastest.

Perhaps the strangest thing about this recent growth is that it must almost all have happened by conversion. The one-child policy, if nothing else, ensures that Christianity is not spread by large families. New conversions to Christianity in China are mostly found among the educated and striving classes. About half of the country’s few human rights lawyers are Christians, as are many of the leaders of the pro-democracy movement in Hong Kong.

The Communist party, like Henry VIII, wants to decide who runs the church in its country

This growth means the real fight is not over whether China will become a country with a significant Christian presence, but who will control the burgeoning churches.

The Vatican knows this well. I have been told by insiders that the strategic thrust of Pope Francis’s diplomacy is all directed eastwards, towards the emergence of China as a great religious power. Chinese relations with the Vatican have long been fraught because of conflicts over the control of the Church, and in particular the control of appointments. The Communist party, like Henry VIII, wants to decide who runs the church in its country. The Pope, now as then, is not going to concede the point.

This is one reason why the great majority of Chinese Christians are Protestants of one sort or another, most deriving ultimately from Presbyterian missions in the 19th and early 20th centuries. The decentralised structure of this form of Christianity helps it to grow and spread, but also makes it much harder for governments to cut lasting deals with it. That’s the same kind of problem European governments face with Islam: who are the leaders?

Some of the churches attacked in the most recent wave of persecutions have been official and state-sanctioned members of the “Three-Self” movement, a Protestant denomination that is meant to be entirely under government control (many of the churches have CCTV cameras facing the pulpits, to check the sermons for political unorthodoxy). All this suggests a party that really does not know what to do. Marxism is emptied of content in today’s China, and capitalism alone will not supply big collective dreams. Nationalism is too dangerous. But Christianity cannot be entirely tamed. Perhaps the most striking statistic in this story is that Christians now make up about 5% of the Chinese population. That is rather more than the proportion of Muslims in Britain as a whole. It’s about the level when religious minorities become too big to ignore, and yet too small to feel secure. This week’s outbreak won’t be the last.