The notion of the philosopher's stone concerned the attempt by alchemists to discover a substance that could turn base metals into gold or silver. The equivalent of this in war has been the endeavour to achieve victory at minimal cost relative to one's ambition, to realize strategic objectives but without the high political, human or financial price tag that typically accompanies violent contest, or, at a wider societal level, to use war to achieve national ends but in a manner that does not place significant demands on the people. Indeed, a recurring theme throughout the history of war – although not necessarily always the most prominent one – concerns the efforts of belligerents to somehow limit, minimize or evade the various liabilities associated with its conduct. Vicarious warfare is an extreme form of this strategic alchemy, and contemporary America is its most enthusiastic guild, presently engaged in its own military magnum opus toward this end.

Of course, in principle, the most important cost of war to avoid is defeat. The prospect of this eventuality is a major factor causing actors to commit fully to the fight, however arduous it may prove and however great the energies, resources and sacrifices it may demand. Where a community's survival is at stake there may be a tendency to ‘pay any price, bear any burden’. But in wars fought for more limited objectives – the majority in history – there is a greater tendency to engage in cost-benefit calculations. The rewards that might be had from war are set against the possible consequences of failure and the potential price of the whole endeavour, typically measured in blood and treasure, even if objective measures are almost impossible to determine or predict accurately in advance. The resistance that the adversary is able to mount and the costs that accrue will cause belligerents to reassess where the balance lies, but the basic logic behind this lethal ledger nevertheless retains its relevance. Accordingly, the more that costs can be reduced relative to the prospective gains, the better, especially if lowering the former does not entail any simultaneous scaling back of the latter. This is all perfectly understandable.