If you accept all of the other irrational tenets of the religion, then why not accept the idea that god wants you to bomb children? And if you believe that's really what god wants, then who are you to refuse?
People will believe whatever it is that they want to believe, religious texts can be twisted to support just about any position, or the opposite to that position.
I think the outermost comment made a great point that religion is basically a tool to manipulate people, to make them make irrational moves. After all, if you want people to move rationally, you make rational suggestions, otherwise even if people are doing the right thing, they're doing it due to irrational reasons.
When people are made to do good things due to irrational reasons, they may be made to do bad things due to the same or similar reasons the next day. A religion can teach to love and it can teach to hate. Why not discard such a tool and let people make their own decisions with better reasoning other than fear/love of God or wanting to have a better afterlife?
There are several elements here. First, most people are not rational, and they can't be motivated by rational deduction. Most people simply do not have the intellectual horsepower to overcome their emotional perspectives and rationalize themselves into good decisions, even when the essential data is present. This invalidates "just be rational" as a practical solution to social welfare.
Second, the essential data is rarely objective or complete. There are very few datasets where a subjective value judgment on some information can be avoided; if you incorrectly devalue some data, your "rational decision" can turn out to be very problematic indeed. So not only are most humans incapable of performing basic rational deduction, they also often lack the perspective necessary to adequately value a subjective dataset, where "adequate" means interpreting it to be compatible with general social cohesion and happiness.
The tried and true traditions of the previous generations of a successful society may err in some smaller things, but in most things, they will be reliable. Young adults (< 50) often lack the maturity and perspective to properly understand the decisions they're making. They'd do well to listen to their elders and try to learn from them.
All of this culminates in "religion" or something very close to it, and it's essential to social stability. If you don't provide one, a replacement will automatically generate. People will find and adopt a belief system as absolutes. You can see this in the "secularist" society of today, that adopts what they perceive to be "scientific consensus" as effective religious tenets, or in the "social equality" segment that adopts their interpretation of "diversity and equality" as effective religious tenets.
I suspect that to those perpetrating all these activities their actions seem perfectly rational. It is to us that they appear irrational. To me they are crazy, to them I'm crazy. But once we start down that road it's just a small step to demonization and saying 'bomb them all' and that's really not a solution that has my vote. So rather than resorting to those methods and getting everybody (including Christianity) up to the standard required for scientific rigor in their thinking we're going to have to walk a different path. Religion is - for better or worse - most likely here to stay and any solution that includes abolishment of religion, no matter how welcome that would be to me personally if it happened - is probably going to achieve the opposite of its stated goal.
