There won't be much to save or from which to rebuild once the fire is out. Even though the walls of the cathedral are of stone, the heat of the blaze will weaken the mortar and the stones themselves. Even if they don't collapse, they may be unsuitable to "build on" afterwards.
An accident,
or...???I'm wondering if that may be possible to ascertain with even the best investigative techniques after a fire of that intensity. Perhaps a worker/eyewitness will come forth with information as to how the fire started?
If the muzzies know what's wise (they usually don't), they won't celebrate this even if it was only "an accident". Doing so may turn a good number of native French (who may to this point have been passive) against them, in ways that may not be peaceful.
Watching Notre Dame burn is like watching Western civilization go down in flames. A harbinger of things to come?
A couple of pics (posted full-size for clarity):
Adieu...