In War in Human Civilization, Azar Gat describes the early modern military revolution:
Armies greatly expanded and became more permanent; they were increasingly paid for, administered, and commanded by central state authorities that grew progressively more powerful; similar processes affected navies, with which the Europeans gained mastery over the Seas.
A world held together by feudal ties transitioned to one dominated by institutionalized, absolutist monarchies whose powers expanded with the scope of war — and, as T. Greer explains, this wasn’t just an early modern European phenomenon:
Small armies organized around noblemen on horseback are replaced by gigantic armies of massed infantry led by professional generals. Reasons of state supplant chivalry in determining the course of battle; court ministers work closely with kings to establish the bureaucratic machinery needed to wage such wars and determine the national interest. Complex strategies and protracted siege warfare become the new norm. All of this describes what was happening in Early Modern Europe — but also what happened in pre-modern China!
The parallels between the Chinese Warring States Era and its pre-modern European equivalent do not end here. The Chinese Warring States Era gave birth to the Chinese strategic corpus. Many historians of Western strategic thought begin with the strategic theorists — such as Niccolo Machiavelli and Cardinal Richelieu — of the “European Warring States” Era. Unlike the strategic thinkers of Western antiquity, these men did not plant their theories in broader historical narratives, but devoted entire treatise to strategic themes. They drew on the histories of the classical era, but their approach was more similar to that of the ancient Chinese thinkers than the Greek philosophers and historians which they esteemed so highly.
What accounts for these similarities? What follows is not a comprehensive review, but a few tentative explanations that I personally find convincing:
A Scattered System of Warring States: War has been a constant in Chinese history; in many ways China has always been a warring state. Less common is its division into warring states. Both premodern Europe and ancient China were host to vicious polities divided in a desperate bid for survival. There was no world spanning empire; all roads did not lead to Rome. (Or Luoyang, for that matter). There was no universal center of learning or prestige that all intellectuals passed through before their voices could be heard, nor was there a single governing authority with power to clamp down on thinking it disapproved of. The decentralized political system of both eras allowed intellectual movements to flower without serious interruption. The competitive nature of this system piled fuel on the fire, for dueling states that refused innovation — be it scientific or strategic — faced annihilation.
The Rise of the State: Modern political scientists often date the creation of the modern-nation state to premodern Europe. However, almost all of these developments (the exception being institutionalized banking and finance) are closely paralleled in the Warring States transition. These institutions did more than increase the number of men that could be thrown into battle; they changed why wars were fought and what wars were fought for. The strategic logic of war between states was fundamentally different than that between feudal lords. Ideas like “national interest” or “reasons of state” made no sense in a society where there was no real distinction between international relations and interpersonal relationships. Treatises explaining how to use military power to attain national goals have no purpose when there is no nation.
Absolute Monarchy: The rise of absolute monarchs had various effects on European and Chinese societies, many germane to the creation of strategic theory. Alexis de Tocqueville remarked that “French kings have shown themselves to be the most energetic and consistent of levelers. When they have been ambitious and strong they have striven to raise the people to the same level as the nobles.” A similar statement could be made about the kings of the Chinese warring states. As kings in both eras extended their control over their realms, they systematically replaced warrior nobles with professional soldiers and ministers. In both eras these men produced treatises on statecraft and soldiery and in both eras men of their rank were the primary consumers of such. The rise of the monarch affected strategic discourse in another subtle way. In the classical city-states of Greece and Italy, matters of state were discussed in the forum or the agora before public audience; feudal systems and tribal confederacies, in contrast, placed emphasis on formal oaths and war-meetings. In both of these cases decisions were made publicly. Those who wished to influence policy (or as was often the case, justify it) did so by way of oratory. Not so in the world of the absolute monarch. Decisions made by kings and emperors were usually made in private. There was little need to justify these decisions in a grand public setting. Those who wished to influence policy did so through personal conversation, correspondence, or official petition. The strategists of both systems were not orators or debaters. They were writers. This partly explains why we have their writings today.