Is it possible that religion is more popular in the most (e.g., the USA) and least capitalist (e.g., Afghanistan) areas than the areas that fall inbetween (e.g., the EU, Japan, China, etc.)?
[WS:] It is possible, but it matters a lot what kind of religiosity it is and how it relates to other knowledge systems that are available in a particular society. In a primitive rural society religion may be the only knowledge system available, so the choice is really this or nothing. Consequently, adopting religion in such a situation is a choice of the highest level of explanation and intellectual understanding under the circumstances.
In countries like the US, however, many different knowledge systems are available that are far superior to religion in their explanatory ability. In this context, embracing religion is tantamount to the rejection of those other superior knowledge system, and it is often an expression of obscurantism, anti-intellectualism and gutter populism. It is quite obvious to me that evangelical religiosity in the US is not really a choice FOR spirituality, but a choice AGAINST urbanism, intellectualism and high culture. US evangelicals are religious not because they love god or other deity, but because they hate urban liberals and their knowledge system.
In this context, a religious man in Afghanistan is probably a sage, whereas a religious man in the US is probably an illiberal philistine.
Moreover, the kind of religiosity also matters. Religion can take many different forms: it can be a philosophical reflection, an ethical system, a repository of customs, tradition or art, a forum for socializing, celebrating life events, bonding etc., a refuge from suffering, an ideological steamroller to enforce social conformity and suppress dissent, or a battle cry to mobilize troops for combat. Although all these forms are usually present in all societies, some may be the leading tenors in different places and in different times.
In my opinion, the battle cry to mobilize troops for combat against various "vices," and the steamroller to enforce social conformity and suppress dissents have been the prevailing tenors of the US-style religiosity and also Islam. On the other hand, religion as a repository of social tradition and a forum for socializing and celebration of life events is the dominant tenor in Latin America, Africa, Eastern Europe and parts of Asia.
Wojtek