Does religion make armies stronger?

[Thumpalumpacus]

No. It makes them weaker. Religious soldiers don't think, they just do things. Religious soldiers will die to impress a non-existing creature thus weakening the strength of the entire army.

This is precisely why it gets stronger - They don't think and just obey, live slaves. There's no difficulty in sacrificing lives for the cause.

Soldiers don't die for gods or kings or countries. They die for their buddies on the right and the left of them.

I was not a combat soldier; I was a firefighter in the Air Force. But I would have preferred dying before the shame of letting one of my brothers down when he needed it most.

Also, blind obedience is not a great soldierly quality. One of the reasons Germans kicked so much ass in two world wars against overwhelming coalitions (albeit losing both, they did so with a kill rate that far outsripped the Allies, in both wars) was that they devolved decision-making to the lowest possible level. In other words, they didn't want preprogrammed robots, they wanted thinkers who could respond to the exigencies of the moment with the battle-plan in mind. Rommel, for one, earnt his cache in the Reichswehr by capturing a mountain with a single company, defeating a division in the process, by going totally outside plans. There are many, many other examples of how the Germans used individual initiative to defeat larger forces. The American Army trains its folks that way as well today -- a tribute to German doctrine of "the man on the spot has the best view."

Robots aren't efficient fighters; they apply one-size-fits-all tactics to situations which are inherently chaotic and mostly unpredictable.

The willingness to die for one's cause is no measure of military efficiency. Don't mistake the two.

In my opinion, any greater cause people believe in, whether it's a religion or a noble or evil ideology, can work as a motivating factor for armies. Anything can, really. If my soldiers feel horny and I tell them they can rape everyone after winning the war (and they are evil or indifferent enough to rape a bunch of people) they'll get motivated.

Motivation is important, you're right. But in terms of personal soldierly qualities, things like discipline, training, and espirit de corps -- the bonding you have with your fellow soldier, no matter the cause -- are more important. Religion delivers motivation, to be sure, but it is not the only motivator. And that doesn't count tactical, strategic, material, and logistic factors.