It's not so much about terrorism as it is simply about conflict between liberalism and small government on the one side and sharia and authoritarianism on the other. Now here's an analogy instead: If you pay someone to be your friend, then they're not friends because they love you, they're friends with you because you pay them money. You can either have a welfare state or open borders. Choose. Welfare state or open borders. Because if you have both, people will come to liberal countries not because they love western values of laissez faire and freedom of speech, but because of monetary subsidies. The only colour money sees is green, I don't give a rats ass about who sells me my tortilla, but I do care if they try to fuck with free speech in any way. Or try to increase the authority of the government. The alt right are a bunch of edgy racists in their moms basements (and not the leftist use of the term meaning "republican", I mean genuinely bigoted), but there are legitimate arguments. The Christianity argument doesn't hold much if you don't care about religion one way or another like me. Yes, you're right, they're both stupid and terrible, but Christianity is not political in the west. It is completely irrelevant and christians are regularly made fun of in pop culture. Whereas islam is very much political and actually has a huge influence on the societies in islamic countries (something ridiculously high like 80% believe sharia should be implemented according to the respected Pew Research, seriously look it up). Both are irrational.