Leftists live in a completely different paradigm from you and I, which is why this problem will never go away so long as they are in power. 

This paradigm consists of, above all, equalism. All races are equal, all cultures are equal, all religions are equal. When you come from this place of equalism it becomes blasphemous to point out anything that contradicts this egalitarian assumption. 

It goes like this, 

- "Muslims are the same as everyone else, it's just a few bad apples causing the problem, therefore we can't criticize Islam for that would be criticizing innocent people and propagating hate against them". 

- "We should allow people for all societies into Canada because they will all contribute equally to society because we all have the same temperament, work ethic and IQ".  

- "Having people naturally segregate into their own smaller communities within the big cities of Canada, creating a society which there is no predominate culture or identity is a good thing.