Really, the best that can be said about religion is that it has certain positive side effects. It can help ease stress and promote happiness on an individual level, and encourages altruistic activity to a certain extent. However, these things can also be achieved using secular methods, without all the negative things associated with religion, such as dogmatic adherence to arbtirary doctrines, many of which are socially harmful.Ziggy Stardust wrote:Think about it in terms of religion, and the numerous atrocities committed in the name of Christianity. Just being Christian or religious in and of itself is not evil. However, the right combination of ignorance and prejudice can cause your religious inclinations to create all sorts of evils. It is overly simplistic to just waive your hand and say that religion is bad, especially when closer studies reveals it becomes difficult to separate these actions from extant social, cultural, political, economic, and military factors that are intertwined.
Similarly, the best that can be said about nationalism is - again, that is has certain positive side effects, such as encouraging civic responsibility and perhaps reducing antipathy among subgroups. But it's really not clear if this is worth the associated "us-versus-them" mentality that inevitably falls into place alongside a nationalistic spirit. A more general sense of social responsibility to all humanity collectively is obviously preferable, but unfortunately this kind of sentiment is not as powerful as nationalism because it doesn't nicely tap into our pre-existing tribalistic tendancies.