Hmmm, I don't want to enflame anyone here, but I do think that whatever it is about the human mind that can be hijacked by religion, can also be hijacked by other "secular" concerns, such as animal rights, environmentalism, global warming activism and vegetarianism/veganism.
However legitimate these issues are (and they are), the part of us that ends up becoming fanatical, to the point where we behave irrationally, can also be aroused by these things. When you see people from the ALF blow up a research lab, or PETA taking advantage of the brutal murder of a Greyhound passenger to tastelessly get their message across, what has happened in their minds is more or less the same as what has happened in the mind of a fanatical religious believer.
To this extent, I can agree with the designation of "religion" that some people use to describe the concerns I mentioned before. Not in the theological sense of course, but in the sense that some people can elevate the importance of maintaining the integrity of the belief above the importance of human well-being.
Another aspect of some of these issues that leaves a bad taste in my mouth, and often reminds me of religion, is the sense of moral superiority that is projected by some of the more fanatical activists. As humans, we wish to be viewed as ethical, moral beings, but some people get carried away in trying to achieve this. When fundamentalists rail against same-sex marriage, drinking alcohol, sex in general, abortion etc, they are hoping that, by doing so, people will regard them as morally superior to others who hold a different stance on those issues.
The same could be said for some people who fight for non-religious concerns. The source of religious irrationality is not religion itself (although I do think they are all founded on falsehoods), but the fact that human beings are not entirely rational. This is why it is important not to think that you are automatically rational, simply because you have abandoned religion.
