We cannot skip over the fact that there have been many injustices done by the church in the name of Christ. Dawkins and his ilk are correct in saying that religion has been one of the major threats to world peace, yet the contribution of societies that deny the existence of God to war and terror is also undeniable. Soviet Russia, Communist China and the Cambodia of the Khmer Rouge are all examples of societies that tried to stamp out religion yet committed unbelievable atrocities. This tends to make me think that it is not religion, but something inherent in mankind that makes him behave so.
It is also true that individual Christians are more badly behaved than some non-Christians. A church is more like a hospital than a museum - it is there to rescue the morally lost rather than to preserve the saints. Many religions have as their aim to follow a set of rules; they always aspire to do better. True Christians are people who have realized that the rules cannot be kept and instead throw themselves on the mercy of the court. We are saved by grace (undeserved mercy) not by deeds.
Nevertheless, Christians have been responsible for many of the social improvements that the world has seen. In the highly stratified Graeco-Roman world, Christians mixed people from different races, classes and backgrounds, though in society the poor were despised, Christians gave generously to the poor of their own and of other faiths. Women had very low status in society; it was very different among Christians, not for them the high levels of female infanticide, forced marriages and poverty that were common among Roman women. During the urban plagues off the first two centuries it was the Christians who stayed and cared for the sick at great risk to themselves while the high and mighty fled the city. I need not say more about the evangelical revival of the nineteenth century, when great reform movements ended slavery, got children out of coal mines, improved conditions in factories and started orphanages. Let it be agreed that for all that the church has much to be ashamed of, when it was closest to its masters intentions it was a force for good.