You have searched back 60 years to try to drag up some sort of proof in an attempt to expose some simmering rift.
That bombing was not a religiously motivated one (I hope you realise this, otherwise please do more study during the school holidays) - it was not aimed at Christians and in contrast to the daily bombings of Christians, Jews, Buddhists, Hindus and others by those in the name of Islam.
The real breach appears to be in the mind...
...keep searching and one day your eyes and your mind may be awakened...one can only hope.
Turn away from mischief. Again and again, turn away. Before sorrow befalls you. Set your heart on doing good. Buddha Dhammapada
xgrasshopper, suggest you focus on the more critical question of the 21st century:
