I don't think the comparison is applicable..  Certainly there was a time when Christianity experienced its share of inter-sect fighting but that hasn't been the case for hundreds of years 

The only recent conflict in Ireland where the factions were referred to as Protestants and Catholics had nothing to do with religion,   It started out as a religious conflict but by the time it came to the violence is was about something else entirely, loyalty to Britain.

Islam has struggled with inter-sect violence throughout its history and unfortunately it continues today.  Can you name one Muslim majority nation that has avoided this struggle and all religions co-exist peacefully together?

Secular nations update their laws to reflect changing times without having to question their religion, 

Non-secular countries are stuck in time, as are their laws because questioning their religion is unacceptable and in many cases illegal.

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