Massive migration of immigrants and refugees with no employable skills, don't speak the language, live in Ghettos and no attempt to integrate.
Given these conditions, it doesn't matter where they were born, they don't see themselves as part of the society they are part of and reject the values of the country they inhabit.
And I know the progressive narrative is that every terrorist is birthed in the country they attack and that they are simply angry because the West is repressing them, etc, but that is simply not the case. Too many to list here, but you can Google. All of them, born in country or in the Middle East, have been radicalized and often trained by Middle Eastern terror groups.
Canada cannot go down that road.