Liberty&Power blogger William Marinara's mainpage article on the relationship between faith and imperial decline (as well as L&P'er Arthur Silber's recent post on deficits and power) brought to mind another example of an empire whose shift towards faith over reason coincided with decline. That it's not a simple cause-effect relationship does not greatly lessen the impact of this particular comparison because many of the crucial factors at play then are at play now. It's probably out of date, and I assume my expert colleagues will correct my missteps, but I was very struck by the parallels between the US situation now and the situation of the medieval Islamic Empires, as described by J.J. Saunders (excerpted in Reilly).

Saunders describes the 13c decline of Islamic/Arabic civilization as a result of four factors:

1. Invasions (particularly mid-13c) and unrest, culminating with the Mongols.
2. Decline of urbanism and the mercantile economy, resulting in semi-feudalism supplemented by (already common) widespread slavery
3. Loss of linguistic and cultural unity as Arabic lost place of pride to Persian, Turkish and other more local languages [Saunders doesn't make a strong case in the excerpt for this as a causal factor]
4. Failure of rational and secular scientific thinkers (e.g. Ibn Rushd/Averroës) against mystical dogmatic and fundamentalist textual approaches (e.g. al-Ghazali) leading to a decline in interest in"the profane sciences." [This is the most important factor, according to Saunders, though the first one has to be a close second]

Compare this to our current situation:

1. Nobody is invading us, but our economic and transportation infrastructure is highly vulnerable to panics. Look at how much auxiliary damage was done to the economy by 9/11, SARS, CJD. Look at the upward pressure on gasoline prices produced by attacks on Iraqi oil infrastructure. Frankly, terrorists have been pretty unimaginative in this regard, though the recent al-Qaeda-related attacks on Israeli-frequented resorts in Egypt come close.
2. Our current accounts deficits and the weakness of the dollar, the decline of manufacturing (not entirely a bad thing, as long as other productive sectors of the economy are rising), cultural attacks on urban culture and demographic shifts to exurban/suburban life, oligopoly and corporate feudalism....
3. Diversity is less of concern to me than outright polarization. Common language is useful, but not as useful as common values and, to some extent, cultural references."Multiculturalism" in its political form is troubling, but so is the 'echo chamber' effect of politicized news media, suburban life, homeschooling, etc.The Habermasian"public sphere" is fractured.
4. Left Behind, anti-Evolution crusades, political campaigns that hinge on protestations of faith, stem cell research limits, NSF funding cuts, textual literalism and ecstatic devotionalism in all the major faiths....

I tell my students, when we study the Roman empire (and repeat it for the Byzantines), that you can be in comfortable decline for centuries. Doesn't mean that it isn't decline. Just that it might take a while before the vector becomes clear.