As I see it, there are two very large megatrends that are crossing in the 21st century: the decline of religion (in terms of credibility and the number of serious practitioners it attracts) and the urbanization of humanity.
Demographers tell us that, by the end of this century, only 10% of of humanity will live in rural/agricultural areas, and 90% will live in cities. 150 years ago, of course, these numbers were reversed. The traditional religions evolved out of the logic of patriarchal and agricultural low-tech societies. The feminist, urbanized, high-tech world is a shock to the traditional systems of meaning. It results in religious fundamentalism as reaction.
Fundamentalism is to religion what Trump is to politics: a simplifier in the midst of crisis.
The irony is that, in their emotional and intellectual narrowness and fear, religious fundamentalists don’t find solidarity with one another, but clash. The clash between fundamentalist forms of Hinduism, Christianity, Judaism, and Islam is a product of urbanization and globalization. They are ill-adapted to their new environments, and so they are eating one another in a zero-sum game, defaming and imploding their credibility even as the secular trends progress.
The broken wheels squeak loudest. That’s why I say there is not a dime’s worth of difference between the fundamentalist religions; that their fighting is a product of the narcissism of small differences. On the same grounds of irrationality and tribalism, they’ll go on demonizing, fighting, and cannibalizing each other. The rest of the world, meanwhile, will continue to evolve toward a more science-oriented, urban, and multiculturally tolerant future.