Sorry, I can’t help you there. I really have no idea what doctrinal differences there are between the shiites and sunnis. To outsiders, there may well not be any major ones. It seems to me it may be more political than anything.
It does bear some resemblence to the Catholic vs Protestant wars in 17th century Europe. Most of those were not about actual doctrinal differences, but rather about political control of the countries involved. I suppose to a non-Chrisitan, the doctrinal differences between Catholics and Protestants, especially groups like Lutherans and Anglicans, seem minor and petty, certianly not worth fighting wars over. Certainly it speaks to the difference between Muslims and Christians; we Christians got over our differences in relatively short order, at least in terms of overt warfare and violence, in comparison to the over 1000 years of fighting that has taken place between the Muslim groups.
It seems to me it may be more political than anything.
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You may be onto something there.