This has been the case for nearly 2000 years.
Are you being serious? Because centuries of Christian dominance in Europe would tell you otherwise.
Roman persecution, other European pagans, Islamic invasions, religious violence in the Reformation, the rise of Communism. Had Hitler been successful he had plans to eventually eliminate Christianity as well.
And then, of course, there is the rest of the world.
No pagans have killed as many Christians for religious reasons as Christians did. As I said, killing Christians seems to be the main Christian doctrine: at least, it is the one thing they all happily do.
Well, pagans were a non-factor in most of Europe for the last millennium, that's for sure.
Well, nor do Muslims, Hindus, Buddhists, etc. taken all together compare in the number of Christians murdered for religious reasons with Christians. Killing Christians is the main Christian doctrine. Historically, if there is a religion of murder, war and cannibalism, then Christianity is it.
You may be overestimating the degree to which Christianity, as a religious faith, is itself responsible for these centuries of heinous crimes. There's nothing in Christian doctrine that legitimizes the crimes committed by countless numbers of its adherents. In reality, the problem isn't Christianity, but rather the cultures that adopted Christianity. Numerous Protestant sects, despite being quite small, were fundamentally opposed to the violence that dominated their societies - such as the Quakers. Whereas, and more numerous, other sects were perfectly happy to engage in bloodshed and conquest while preaching "love thy neighbor as thyself." Even when conducted in the name of Christianity and condoned by Christian leadership, the crimes were those of the political system those Christians largely inherited.
Consider how Christianity in the Mediterranean vastly differed between each ethnic group and their respective cultural traditions. When the Roman leadership converted to Christianity, they justified their expansionism and persecutions of threats to their new political leadership through references to their faith. The persecution and forced conversion of Northern European Pagans was no different; it was for political purposes, with Christianity as the excuse. Remember, at this time the Church forbade Mass to be recited in any tongue other than Latin and for the congregants to have access to Bibles. They used the Roman Church to expand their political power; similar actions were conducted in the Greek dominated East, albeit to a less severe extent. The Levant, Ethiopia, and Egypt also had a less aggressive form of Christianity compared with the Roman dominated West. In Eastern Europe, the Eastern Orthodox Churches preferred the protection of the Islamic Ottoman Empire and the Sultans to the threat of the Roman West. It was the Roman West who even attacked Constantinople and attempted to reconquer the Levant from the Muslims, which largely fell apart due to the Roman Church wanting to dominate the largely Orthodox and Oriental Christian natives. Look what happened in Spain following the defeat of the Caliphate: Muslims were killed, expelled, or persecuted, followed swiftly by the expulsion of the local Jewish populace that took refuge largely in the Muslim lands of North Africa and the Ottoman Empire.
The problem is clearly not Christianity as a faith, but rather the cultural inheritors of the Roman imperialistic mindset. Unfortunately for the world, it was those same people who, due largely to Ottoman blockades that strangled Western Europe's trade with Asia, were compelled to sail around the Middle East and thus discovered, then persecuted and exterminated millions of people, the "new world."
