It seems to me that there are several such threats. The first is old-fashioned tyranny; that's not gone out of business. Eritrea is a very good example. The most terrible persecution of Christians started with the evangelical Christians in Eritrea but has now also spread to Orthodox and Roman Catholic Christians: people being imprisoned in containers, left out in the heat of the day and the cold of the night; torture, beatings, all sorts of things, and the reason, as far as I can tell, is just personal tyranny and the fact that the rulers of Eritrea seem paranoid about these different Christian churches and people. The Orthodox Patriarch has disappeared and no one knows where he is, but this is an example simply of paranoid dictatorship, nothing else. 

Another threat is totalitarian ideology, for example in the form of one kind of Marxism or another. The situation in China is much improved, partly because of the sheer numbers. In 1949 there were perhaps five or six million Christians-Catholics and Protestants — in China; there are now perhaps a hundred million, maybe more, so the numbers are such that they cannot be ignored and their situation, at least in the big cities, has improved in terms of freedom of worship and of witness. But it remains serious in other respects, particularly with the unregistered churches, the so-called house churches, although many of them are so big that you cannot really call them house churches. The situation of those Catholics who still profess a loyalty to the Pope remains serious. Some Catholic bishops are still either in prison or under house arrest and many clergy of that part of the Catholic Church have been in prison, have been tortured or been in labour camps, as have the leaders of house churches. So there is a long way still to go as far as freedom is concerned for the people of China. The other example of these remnants of Marxism is Vietnam, where the evangelical churches have grown exponentially. While Roman Catholic Christianity has been present in Vietnam for a long time and has also suffered grievously at the hands of the rulers, the evangelicals are now finding that the heat is on them and people are being prevented from worshipping, their churches are being destroyed, they are being deported from their villages to other villages and sometimes being detained and fined simply for being Christians. Again and again villagers are told, "In this district you cannot be a Christian." Laos is another example of continuing terrible persecution for evangelical Christians, partly as a remnant of Marxist ideology. 

There are other examples of persecution. As I mentioned earlier, regrettably, in spite of the example of Ashoka, there is the persecution of Christians and Muslims in Burma, sometimes (I am sorry to say) led by Buddhist monks. This is also the case in Sri Lanka, both with regard to Christians and also in terms of the Tamil ethnic minority. The West has a rather idealised picture of Buddhism, but that is not so in Burma or Sri Lanka and some other countries. In India there has been persecution of Christians, again because of the ideology of Hindutva, that is to say, the belief that the only real citizens of India must be Hindus, that others — such as Christians and Muslims  — cannot really be citizens of India unless they become Hindu in some way or other.