
Read Part I Part II Part III and Part IV

One of the more poignant moments in the epic film Gladiator takes place during the opening battle between Roman legions and German tribesmen. The Roman general Maximus and his lieutenant, Quintus, are debating whether their outmatched foe will fight or submit. Quintus opines that “People should know when they are conquered,” whereupon Maximus replies: “Would you, Quintus? Would I?” That’s a Hollywood restatement of Clausewitz’s proverb that “even the ultimate outcome of a war is not always to be regarded as final. The defeated state often considers the outcome merely as a transitory evil, for which a remedy may still be found in political conditions at some later date.”

It seems fitting to close out this series the way it started, with some thoughts from the Prussian theorist. It’s one thing to carry the day on the battlefield, or even to win a war. Translating battlefield success into a durable postwar order is another thing entirely. As Maximus implies, and as Clausewitz declares outright, the victor needs the consent of the vanquished to make the military result permanent. If the vanquished reject the outcome, they set the stage for new rounds of struggle. Should it lose a war along its maritime periphery, China could renew the fight later, assuming the military trendlines go its way, or try to overturn the result through coercive diplomacy. So could the United States and its allies.

Who would hold the edge in a protracted struggle? It depends on what’s at stake in a particular controversy, on the belligerents’ resolve to get their way, and on the resources they command. A passage from Clausewitz we pound home over and over in our seminars spells out the rational calculus of war. “Since war is not an act of senseless passion but is controlled by its political object, the value of this object must determine the sacrifices to be made for it in magnitude and also in duration.” How much importance each belligerent attaches to its goals, that is, determines how many lives and resources it is prepared to expend to reach those goals, and for how long.

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But there’s a corollary: “Once the expenditure of effort exceeds the value of the political object, the object must be renounced and peace must follow.” Once the enterprise starts costing more than it’s worth, statesmen should strike the best peace deal they can and exit the conflict. Whatever sunk costs the nation has incurred are just that—sunk, and written off.

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Or at least they should be. Cutting one’s losses is easier said than done, in large part because Clausewitz’s value-of-the-object equation is hard to balance. What figures do you assign the variables? Quantifying magnitude and duration is reasonably straightforward. Simply tally up manpower, assets deployed and lost in combat, fuel and rounds expended, and other indices of physical strength. Time is, well, time. But what units of measurement describe the value of a political object? What is the objective value of Taiwan, the Senkakus/Diaoyus, the Spratlys and Paracels, and other disputed objects to the contending parties?

There’s no single answer. The worth of such things is subjective. Intangibles like fear, spite, and the thirst for honor and renown color perceptions of the political stakes. Passions tend to drive up the perceived value of the object. If one antagonist assigns its war aims inordinate value, it will expend substantial resources on those aims’ behalf for a long time. If both antagonists judge the stakes vital, escalation is likely. And if allies evaluate their mutual objectives differently, they may find it hard to reach consensus on strategy.

So a fictional Roman general was right. People often don’t know when they’re beaten, or refuse to admit it. They may postpone a final reckoning rather than accept defeat. U.S. and allied leaders must think ahead to the immediate objective, how to end various contingencies with China on favorable terms. But they also need to consider what will come next. China isn’t going anywhere—and so managing the peace in Asia demands the long view.