Can you honestly say that the crusades were not based on pure hatred of the Muslims by the Christians and vice versa. A good number of wars have been started by hatred or quest for domination. The crusades was all about who dominated the Holy Land...and the fact that there was hatred and mistrust of the muslims by the middle age christians especially in regards to their better technology at the time and skin tone...
As you may have argued that war is different from murder in the case of the Protestans and Catholics or Muslims and Christians, it is interesting to see that it is rather easy for you to merely brush christian to themselves and to others out of their faith as being within the natural limits of war. Of course, war is not equal to murder....it is just substantially involves a hellavu lot more souls meeting an untimely death but is somewhat justified, I guess.
The last time I checked the Irish catholics and the Bristish protestant authority were not exactly shaking hands....need it be said there is an element of hatred towards each other and the desire to maintain domination by the largely protestant British government who seemingly do not want let go of their powers over the Irish/Scots.
As for a more recent example, who else but GW? using his faith as a permission slip to invade a non christain nation in the self-righteous name of extending democracy or more like shooving down the Iraqi nation all in the name of opening up the oil fields in Iraq to the benefit of his cooporate supporters.
In short, just as you advocated that Africans need to take responsibility for the things that they may have done, it is imperative that Christians as the good book suggested, should remove the moot in their own eyes first.
Christianity is just as guilty or even more so because of their own standards (i.e. judge ye not, as you will be judged by the same yardstick you used to judge...paraphrased)as the African traditions.