The first stage of the shrinking was cultural. Europe had already begun turning away from glorifying war even before the treaty was signed. The trenches of the First World War had exposed something humiliating about modern combat: War was no longer heroic. It was industrial.
Factories produced shells the way bakeries produced bread. Soldiers were not knights; they were replaceable components inside a machine designed for attrition. The public reacted accordingly. War poetry changed. Same with war literature. Propaganda grew subtler and people began arguing about wars rather than celebrating them. The sword, in other words, began losing prestige.
Words began gaining it.
Political speeches started shaping national destinies more effectively than military victories. Journalists discovered that a well-timed headline could destabilize governments. Intellectuals discovered that ideology could mobilize entire populations without firing a single bullet. None of this looked like Clause One being implemented, but it was. The sword was shrinking but no one noticed because the process felt natural.