What is technology really good for, militarily?
I began my professional career more than 60 years ago when at age 19 I became an engineering assistant at Hughes Aircraft, working on development of the MA-1 airborne fire control system, a very advanced bit of technology for the time. Ever since then, with the exception of a few years at sea with the USN, I have been involved in figuring out how develop advanced systems of many kinds for military purposes and how to employ them.
What was it all good for? What truly is the role of technology in military affairs?
In his very interesting and thought-provoking book, War! What Is It Good for? Conflict and the Progress of Civilization from Primates to Robots, Ian Morris talks about "Red Queen" races in war analogous to those in biology, with each side endlessly striving to gain technological superiority and with their gains tending ultimately to cancel one another out. But as Morris observes
Each revolution [in military affairs] was a race between offense and defense, but ... war was never a case of what evolutionists call the Red Queen Effect. The race did not leave everyone in the same place, because it transformed the societies that ran it. Every revolution required Leviathans to get stronger... 
Morris is dealing on millenial scales but the principle applies at shorter scales also; the technological races of the two world wars, the Cold War, and even the smaller quasi-wars since then have manifestly brought about tranformation of the whole technolgy systems of the opponents, and even some societal effects as well.
Military technology involves a kind of Ricardian principle of comparative advantage as well with each participant seeking to gain most in technological fields in which its resources are relatively most productive. It is clouded by the lack of a market to provide valuations but war itself does provide a clearing mechanism of sorts. Thus in the World War II era the large scale and high productivity of its auto industry provided a capability that could be and was deployed effectively by the United States in many seemingly diverse technology areas. Similarly with digital electronics in the Cold War era.
The dearly-sought objective of the military technologist is asymmetric advantage gained through an innovation that the other side has failed to anticpate and preferaly is incapable of responding to effectively. A well-known modern example that I had something to do with is what is popularly known as radar stealth. The United States was clearly first in the field (even though some of the important contributing technology was Russian in origin!) and others are only now striving to duplicate capabilities the US has enjoyed for several decades.
Stealth is an asymmetric technology, generally more valuable for offense than defense. Many of my colleagues believed fervently that it was a war-winner, that the Lockheed F-117A together with a projected long-range stealth bomber (which after many twists and turns eventuated in the Northrop B-2A) would revolutionize warfare and assure U.S. victory. A number of senior USAF officers were highly skeptical and quite opposed to buying the F-117A. The objections were not entirely groundless and it is clear that the F-117A and ATB did not in themseves add up to a war-winning capability, even if bought in the quantities that their proponents sought. On the other hand it is also clear that they were far more valuable than many of their critics gave them credit for. Stealth was then a technology that could make a real difference, but not all the difference.
To employ stealthy strike capabilities most effectively requires a substantial specialized infrastructure as well as costly force assets. On the other hand, to defend against stealthy strike is extremely demanding and costly. Of course the defender may choose simply to absorb the damage that stealthy strike can inflict, or may have no real capability to defend, but this stance too has high costs. Thus stealth raises the price of conflict, but more so for the defender than the attacker. I see this in terms of tilting the underlying strategic terrain in favor of the richer and in favor of the offensive.
The effectiveness of stealthy vehicles depends on the employment doctrine, naturally. Doctrine starts with ideas about employment that are developed and elaborated upon. As is true of most technological innovations, ideas about how to make stealth and how to employ it coevolved; attempts to assign priority to the one one or the other are inherently futile, at least in the initial stages.
In very broad terms this is the story of virtually every other military technology as well, from hurled rocks and sticks on down to the present. Some technologies have been offense-favorable, some defense-favorable, and others more or less equally beneficial to offense and defense. Many have raised the cost of war, at least to some degree.
What about transformative capabilities, technologies that entirely disrupt the balance of military power? From what we can tell (subject to a lot of uncertainty) the charriot seems to have been transformative, and also the later introduction of cavalry. But that was all a very long time ago and over the past two millennia and more it is pretty difficult to pick out any technological innovations that were truly transformative on a grand strategic scale. War of course has been entirely transformed many times over in the course of the past twenty centuries, but none of the innovations that have contributed to the overall transformation have sufficiently unilateral or sweeping enough in effect to entirely upset the balance between nations.
But what about firearms? Were they not radically transformative? Did they not propell the dominance of the West? The first clear evidence for firearms in Europe dates from the 1300s and it took only a few decades to demonstrate that the Medieval curtain-wall fortification was vulnerable to siege cannon, leading to its replacement with low-lying "trace italienne" fortresses. The expense both of siege guns and especially the new fortifications arguably played a role in European political and economic development, but this was scarcely a revolutionary transformation in itself. Firearms did come to dominate the European battlefield, but only in the late 1600s, three centuries after their introduction. And it took further major innovations before European-style forces could prevail against horse-nomad forces in the steppes. Arguably, all this occurred only because European states had the imperative and the means to contest for territorial supremacy in Europe over the four centuries that it took for their forces to develop the capabilities to dominate Eurasia. Certainly the outcome of the Crusades and of Ottoman-Western struggles in and around the Mediterranean in the intervening period suggest that it was not until the late 1600s, at very earliest, that European forces enjoyed a significant advantage. Thus I would argue that firearms were not in themselves radically transformative, despite the potency of magazine rifles, automatic weapons, and field artillery.
Yet no one would deny the significance and power of these and other firearms-related innovations. Nor those of rail transport, steamships, aircraft, radar, radio, and a host of other innovations. Each changed the underlying terrain of war in certain circumstances and conditions, and demanded greater resources and stronger organization to gain maximum benefit.
I think this insight about the effects of technology can point to better strategies for technology development. I expect that it will be necessary to formalize it as a mathematical model for best results and have some ideas toward this end. But for now I want test my ideas out further with historical cases, and will welcome comments and suggestions to this end.