Strategic grandmasters would upbraid Ukraine’s leadership for hurling an offensive into the Russian border district of Kursk. Sure, Carl von Clausewitz, the Prussian soldier-scribe of everlasting renown, countenanced opening secondary theaters or operations under certain circumstances. But he did so grudgingly. Clausewitz cautioned commanders to divert forces only on a not-to-interfere basis with success in the primary theater, which after all represents the theater of greatest consequence as the leadership defines it.
This is sage counsel. If nothing else, strategy means setting and enforcing priorities. This takes self-discipline. It makes little strategic sense to hazard what matters most for the sake of something that matters less, no matter how beguiling. For Ukraine—a combatant that stands in mortal peril—the foremost priority must be to hold as much Ukrainian ground as possible while striving to regain lost ground. Kursk is great from a fist-pumping standpoint. Apart from that its benefits appear lackluster.
As he does for so many martial enterprises, Clausewitz enunciates a simple formula to help the leadership fathom whether to open a secondary theater or operation. Some years ago I took to calling it Clausewitz’s Three R’s, namely reward, risk, and resources. A new endeavor, that is, must not merely promise nice-to-have gains. It must be “exceptionally rewarding.”........