Five hundred years ago, Christianity was as bad (see reformation, st bartholomew's day massacre). Things are much better now. Has "Christianity" changed that much ? The core of the faith is still the same. In my opinion, what has changed is rather all the "other factors" : i.e. when you are literate, well-fed, do not feel oppressed or unjustly treated you are less likely to hack your neighbor to death.
Does that make Christianity a good or bad religion ? Or Christianity now is good while it was bad before ?
I understand what you are saying, but I think I am interpreting events differently.
One last point, if you have a look on the last few hundreds years in Europe, you will find, and I probably miss a few religious wars :
- catholics vs Cathars and various heretical movement
- catholics vs protestants
- christians vs jews
And as the ideology changed:
- monarchists vs republicans
- marxists vs fascists
etc ad nauseam.
I do think the "Us vs Them" mentality is a constant of the human experience, and with or without religion of any sort, we will find new ways to be divided (see hooligans, is there something more stupid that dying for your team ?). And I believe that the debate around Islam is just another epiphenomena that will be replaced by something else in 50 or 100 years.