From a military point of view, one can relate to the castle – any castle – as a complex and expensive technological development intended to withstand attack and to ward off enemy attempts to capture or mount a siege against it. Castle architecture, like all other improvements in military technology, was influenced and shaped by a constant tactical and strategic dialogue between opposing forces. When one side developed a new and successful siege tactic, the opponent countered with a new strategy of fortification that took the edge off the enemy's innovation. This in turn led the attacker to come up with a new strategy for besieging the castle, and the cycle was repeated.

This phenomenon led Hugh Kennedy to write: ‘The development of castle architecture must be seen as the result of continuing dialectic between attack and defence which gave the advantage sometimes to one, sometimes to the other. Only by examining techniques of attack can we come to a real understanding of the architecture of defence.’ In other words, Frankish military architecture reflected not only the construction methods with which the Franks were familiar, but also Muslim tactics of siege and warfare, as well as the financial ability of the owners of these strongholds. And yet, even in his brilliant and innovative analysis of the strategic dialectic between the Frankish castle and Muslim siege tactics, Kennedy hardly refers to the gradual development of this very dialogue over time and space.