Christians are guilty of many crimes throughout history, as are members of many religions. And yes, the Christian faith has been misused to motivate hate time and again, against the direct teachings of its founder. But the greatest underlying sin of Western Christianity, most obviously demonstrated over recent years, has not been expressed by the fringes but the mainstream.
It is a too small sense of 'we'.
In a sense, atheists are right for criticising Christians for how we define who we are. And not just because it is so often just used as a way of distancing ourselves from the embarrassing or horrifying. It is a fault not in how we define what a Christian is, but how we define who 'we' are.
We define this too narrowly: 'we' as a nation, 'we' as a religious group, 'we' as an economic class.
As a universal religion that potentially and at its best can be expressed within (and can simultaneously critique and subvert) any culture, Christianity, with its focus on the New Testament, should never place one race, one nation, one culture above another in any automatic way.
And our failure in this area is most obvious in the way we look at international events. We look at Libya purely in terms of our interests: will the anti-'us' dictator go? Will they have a democracy that resembles closely enough 'our' own? Will it be a threat to 'us'?
We look at Zimbabwe in terms of how upper middle class / white farmers are treated. We look at conflicts as if only a few exist. We think of ourselves as internationally conscious for understanding the situation in Palestine (those of us not drinking the Zionist Christian Kool-Aid) but aren't even aware of the conflict in the Central African Republic and the situation in Ivory Coast. We have only a cartoon understanding about what is going on in Sri Lanka and, of course, have ignored for well over a decade the conflict in DR Congo that has claimed many millions of lives with little comment from our governments and media.
The reason most of us ignore conflicts like Congo is not because we think in the same terms of our governments (breaking the silence on Congo will make mineral acquisition essential to our consumer electronics businesses terribly expensive for us; cracking down on the likes of Rwanda and Uganda as they repeatedly invade Congo will make our alliances with them tricky and bring up issues of national guilt). No, it is because we don't care. Because our 'we' is too small.
This is not an issue of apathy - look how we care about Sudan for the three months it is sexy or East Africa as long as there are starving children on TV. This is a failure to empathise, a failure to identify, because 'we' are not facing this. 'We' never will, because 'we' are wealthy, European, powerful. In humanitarian questions, 'we' are the the ones handing out the food out of the goodness of our hearts. The good guys. This is why we do not care about the death tolls in Iraq or Afghanistan of enemy soldiers, local civilians. They are not 'us'. We'll mourn soldiers from 'our' side but not civilians from 'theirs'.
This would be somewhat mitigated if we were, as a Church, consistent in our approach to the 'us' we cared about. It would be monstrous, but at least coherent, for Christians only to care about and assist Christians, because of some sense of 'duty to our own'. But a significant proportion of the Palestinians whose plight we ignore as so many of us follow the awful John Hagee and his Israeli-aggression-loving chums, are Christians. The majority of the population of Congo is made up of Christians. Our 'we' is apparently too narrow even to stretch to them. Race, geography and bad theology are more important than even the most selfish of solidarities.
The correct response to this is not to rush to the aid of Christians in distress (noble though that is). The correct response for someone believing in a universal religion, in the equally God-reflecting nature of every human being, is to extend the borders of our loyalties and broaden the scope of our 'we'. This is an essential step for Christians, but a rather good idea for us all.