In 2003, before the US invasion of Iraq, there were an estimated 1.2 million Christians living there. Today, that number is less than 250,000 -- an eighty percent drop in less than two decades.

If this trend continues, a religious minority that has been in Iraq for centuries will be gone entirely.

A recent article in The Atlantic by reporter Emma Green describes the plight of Iraq's Chaldean Catholic community and the incredible pressure that they have been under since the fall of Saddam. This not only includes ISIS's reign of terror, but day-to-day discrimination against Christians that is causing so many to seek to leave the country.

Related: Timeline of ISIS in Iraq
Related: Attacks on Assyrians in Syria By ISIS and Other Muslim Groups

Emma Green is a staff writer at The Atlantic covering policy, politics and religion. We kick off discussing the history of Christianity before having a broader conversation about the causes and consequences of the fact that a religious minority is fleeing Iraq in droves.

The plight of Iraq's Christians has key geo-political consequences as well as serving as an indicator of the healthiness and strength of Iraqi democracy itself. This conversation explains why what happens to Christians in Iraq matters to the entire world.

If you have 20 minutes and want to learn why the persecution of Christians in Iraq has global implications, have a listen.

What's up first?

Christians have been in Iraq for a few hundred years after Christ. There is a historic population that have been all over Iraq but heavily concentrated in Northern Iraq. They believe their connection to this land reaches back before Christianity. Christianity is their identity and way of forming their communities, but they also see themselves as a people and nation. That connection to a national identity reaches back before Christianity and forms the basis of their claim to being the original people of Iraq.

Can you discuss the connection to the land in comparison to mainstream Christianity in the US?

There is something really different about the way they conceptualize who they are compared to, for example, Protestant Christians in the US. In the US, it does not matter so much where your building is or where your located geographically, it is about this free floating idea of the church. For the Chaldean Catholic community, they understand themselves through a dialect of Aramaic that is close to what Jesus would have spoken. It has all of these call backs of ways of doing worship which include specific land and buildings that are still important to them and make up their identity as a Christian person. What makes this important is that it opens up this question of what it means to be Chaldean in diaspora. If they believe their homeland is at the heart of what it means to be a Chaldean Catholic, then who are they in another city? That is the reality that the population is facing now. The reality is that most of Iraq's Christians are now living in diaspora.

How were Christians treated in the years of Saddam?

In so many ways, Saddam Hussain repressed several different minority groups. There is a sense in which, however, that those years were ones of stability. His regime afforded protections to the Christian population. There were highly visible advisors who were themselves Chaldean Christians. This allowed Christians to operate under a sense of security, even if they did not have, what we in the US, would consider full liberty. They were not specifically targeted like other groups.

During the expansion of ISIS in 2014, could you discuss the experience of the Chaldean Christian community in Iraq?

During the summer of 2014, ISIS pushed across the Nineveh Plain through Mosul towards the East to the town of Karamles. Emma Green, during her time there, heard that aid workers were assured they were safe. Suddenly, security forces heard ISIS was coming and the town had hours to evacuate. A Priest rang a giant bell to reach all of the people who lived there and move everyone towards Erbil. There were a few people left behind, but ISIS miraculously let them go. They were left displaced in Erbil and hundreds of the residents of Karamles shared an unfinished apartment building, with a roof but only two walls. They soon realised ISIS was going to occupy their town for much longer than a day. It was not until security forces were able to beat back ISIS to the Battle of Mosul that these people were able to even imagine returning home. ISIS was not the beginning or end of their troubles, however.

Can you talk about how ISIS treated the Christian population?

The distinctive thing about ISIS was this targeting of minority populations which have been in the region for a long time and trying to eliminate any claim of legitimacy that they may have to the land and then systematically push them out. It is genocidal almost. There was a big debate whether the US State Department would call this genocidal intent. Christians have a huge advocacy base in the US.

You detail in your piece how in this post-ISIS Iraq there is still daily persecution that Christians feel. Even now after ISIS, so many are still fleeing the country.

We as a global community pay attention when there are exclamation point crises. It is important to pay attention to the slow squeeze too. The way the Iraqi constitution was drafted after the US invasion does acknowledge the right of religious minorities to live in Iraq, but it establishes Islam as the official religion. With that comes practicalities about how Christians are identified. kids of mixed marriages, or children of rape cross religious lines. The lived atmosphere holds many tensions. There is a sense that groups of different religious identity must be separate and will not be treated the same way. Christians think they have to fend for themselves in the absence of a stable government committed to their protection.

This lends itself to the idea of democracy and the failure of democracy.

There is an inflection point about whether Christianity will survive in Iraq. This is sad because of history and culture, but it is tragic largely because it is a test of how thoroughly of the ideals of a democratic Middle East have not been put into place. The inability of countries to sustain diversity and to allow religious minorities to thrive alongside a majoritarian population is a test of its cultural and political will to sustain this commitment to difference and governance. The story is big historically and huge politically for our understanding of what will come next in these countries that are squeezing out their minority religious populations.

Vice President Pence is leading this charge to pour more resources to help rebuild Christian communities. Further, there is evidence Iran is seeking a foothold there. Is there some geopolitical relevance of this piece of territory?

The northern region of Iraq is in a hot neighbourhood. To the East you have Iran, to the West you have Syria, to the North you have the Kurdish independence region, and to the South you have Baghdad. When the US looks at this, they not only see a country they want to retain as an ally against Iran, but they see this swath of territory that it has had a large military presence in that they do not want to fall to American enemies. One theory is that there is a clear dotted line between the sense that the US has an obligation to stabilize religious minorities because of our commitment to religious freedom and the sense that the stability of these populations is a bulwark against the rise of extremist forces and regimes that the US perceives to be its enemies.

What sort of events would indicate that the number of Christians will fall even further?

The first is that, with a comparison to the Jews, many Priests brought this up unprompted stating that once there were Jews in Iraq and they disappeared and now Christians may be next. The most powerful testament was meeting families with either bad luck not being able to emigrate or want to stay, but nonetheless, they all acknowledged that they were trying to leave, would leave, or one day they may need to leave. It is an unstable situation with a very cloudy future. This is not the end of Christianity in the Middle East, there is a possibility that stabilization efforts will work. But, it is hard to imagine a sustainable future after all of this instability.