In a political sense, a "kingdom of subversion" refers to a state or movement that uses to destabilize an adversary. This process is less about open war and more about "turning the values" of a society against itself.
Look at the French Revolution. The subversion of the Ancien Régime was spectacular—the storming of the Bastille, the abolition of feudalism. But the revolutionaries, now the rulers, found themselves unable to rule. They had perfected the art of accusation ( “You are a royalist!” ) but failed at the art of administration. The result was the Reign of Terror, followed by the ultimate anti-subversion: Napoleon’s empire. -kingdom of subversion-