Allow me to be more direct. Just like I hold the shooter responsible for his hostile actions, I hold the operators of that mosque responsible for theirs or the Islamic operators working out of it. There are no passes given on this. It is tragic that innocent lives were lost, but it is an entirely separate subject.
I get that the EU and Canada like to let their terrorist conduct terror operations (Against their own citizens at times.) and then allow them back in as if they did nothing wrong. But that's not how it works. You don't see Christians, Catholics, Jews, Hindus, etc conducting terror operations out of their places of worship. Again, a totally different subject than you make it out to be.
But you both already knew that didn't you?