I haven't watched the video & I'm sure it's horrific but I wont be watching it either.
The thing is though this is extremists as has always been the case you can't pigeonhole an entire religion or race based on an extreme minority you need to target the perpetrators. Australia does need tighter screening to keep the extremists out of this country.
As for the line about thankful variations in Christianity don't go to war like this - you only need to look at history.
30 Year War ? Protestant V Catholic
Charles The Great beheading 4000 Saxons because they wouldn't convert to Christianity ?
There is a pretty substantive list through history.
