Yes, because that is utterly laughable. The reason is obvious to a half-bright child. It's the same reason we now have anti-car barriers on central London, invasive levels of security at airports, bombs going off at music concerts and massacres committed in European cities.
Well, I'd say that without the ongoing story of churches being targeted in France your "huge probaility that it is an accident, with a small chance it was arson" would be the sensible conclusion, but when you add in the knowledge that recently this stuff keeps happeneing, surely your view changes a little? I mean "huge probability" versus "small chance"? Really?
Nah you're just wasting our time. Granted, this is what AWIMB is for. You're constantly banging on about the cultural crisis faced by Europe and using this tragedy, a tragedy for art and for a sense of timelessness, to further your tendentious twaddle. Therefore, while AWIMB is for wasting time, there are limits.