Is it only killings in the streets we need be concerned with though? There are far less dramatic and not at all life threatening implications of a rise in the numbers of immigrants from various cultures and ideologies, that still may be worthy of consideration.
Imagine if we let everybody from the southern us Trump country move up here to Canadia. We would be facing a major cultural problem.
Why should communities and countries and their cultures not have some say over who they invite or allow to join, based on the values held dear by that culture/country?
Again, countries already have policies in place to decide who gets to come in, who they should admit due to their status as refugees, and who doesn't pass muster. Nothing about the current situation necessitates revising those policies. There's actually no such thing as "a major cultural problem" if you have a society where everybody has a voice. If you trust the Canadian system of representative governance, letting a bunch of people with different opinions into Canada should be no reason for concern. If you disagree with what they have to say, vote for people who agree with you and not them.
Trouble is, Penguin et al don't think Muslims are like other immigrants and thus don't think the same rules ought to apply. They think that Muslims are brainwashed dogmatic fanatics who aren't capable of coexisting alongside the rest of us, or that they will do so only as a means to end so they can shove sharia law down our throats.
Their fears are not rational or founded in logic, so trying to approach them logically is a waste of time.