This is just observations and logical analysis so please don't get unneceraily emotional.
Both religions are founded on one-god-one-prophet-one-book, and if one tries to take any of the 3 or question any of the three, the whole religion collapses.
This makes them horribly sensetive about these 3 and their whole psychology works only to defend that structure, and every word in quran or bible. The only way they can stop questioning is to convert the person into the same mindset.
Now Christians call everyone non-believer, and Islam calls everyone infidel, both are queally fundamentalist in their beliefs...so they end-up in clashing as theyr near 50% in any country e.g. in Africa its already happening.
At the world stage its happening too. Its west vs Islam...the equation is pretty much sealed.
Now we just have to watch as they will finish each other.
The best option for humanity is for these two to reform but again...if they attempt to reform their foundation itself collapses,hence they will not.
Well, its tragedy but then let the bloodshed begin...or is it continue?